e-conservation Magazine 18

e­conservationthe online magazine No. 18, February 2011

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The job market… where is it going?

The field of conservation‐restoration has been changing considerably in front of our eyes during the

last few years. Fuelled by the so called ‘crisis’, our profession has been no oasis for the social‐

economic changes that are taking place. Its strongest impact is on the job market, and can be seen

clearly in its deregulation and chaotic existence. The job market is the core of the problem, starting

with the free workforce for internships and ending with the low career prospects for senior

professionals. This system was already established long before the emergence of these difficult

times. However, the crisis has increased the problem to levels never seen before to such an extent

that cultural heritage is in peril.

Of course, the direct reason is the lack of money flow, which is felt deeply by everyone, from large

public institutions to small conservation businesses. A direct consequence of this is that

professionals, especially recent graduates in conservation, are seeking jobs in other areas, either

because after five long years of study they can’t find a position in their area of specialisation, or

simply because other jobs are better paid.

The problems occur when, after having graduated from a degree in conservation, the possibility of

finding a job is virtually inexistent so instead, graduates often seek a suitable internship, which will

hopefully open doors in the job market. This is more often than not an unpaid internship, as the

paid internships are difficult to encounter. It is possible to choose to work for a company but

international or renowned institutions are much better for the curriculum vitae. These are usually

run for educational purposes, and are non‐profit making institutions, thus it’s only natural that for

them, internships are seen as a type of volunteer work. However, in such places interns just replace

other interns, only few of them being actually integrated into the staff. So one moves on to another

internship or a ‘temporary’ job.

Experienced conservators are no better off. As I have noticed, having experience is not necessarily a

plus on the job market. More and more, older conservators in apparently permanent positions have

to be let go, and replaced by interns or (underpaid) early career professionals. This of course allows

institutions to meet their budgets but it also denotes a tremendous disrespect for the highly

experienced professional, not as an individual but as a whole. It also means that cultural heritage

itself is being cared for in a greater extent by less experienced hands. A direct consequence of this is

that these older professionals must return to the job market but for them this is much more difficult

to achieve as age becomes a factor versus experience in a society where youth is perpetually a

prized quality.

This system goes far beyond conservation and it’s very hard to break without a common strategy from

regulators, universities and employers. The true quality of life is nowadays becoming lower and lower

and we are loosing rights that had once been battled for. It is a serious problem with consequences I

cannot foresee but I know they will be a decisive factor for the future of the profession.

Sooner or later something has to give. Why should it be conservation?

Rui BordaloEditor‐in‐Chief

e‐conservation

NEWS & VIEWS 6

ARTICLES

CASE STUDY

32

#culturematters

By Daniel Cull

REVIEWS

Parchment and Leather

Research, conservation‐restoration, craft

Review by Tomasz Kozielec

Seven Years Dedicated to the Conservation of the Modern

Movement Heritage

The Conference Series: “Das architektonische Erbe – zum aktuellen

Umgang mit den Bauten der Moderne”

Review by Maria Bostenaru Dan

NEWS

Website: Google Art Project

Book release: The Orthodox Christian Sakkos

UPCOMING EVENTS

March ‐ April 2011

Infrared Reflectography Using 3D Laser Scanning

By Christian Dietz, Gianluca Catanzariti and Alfredo Jimeno Martínez

A Reflection on the Preventive Conservation of Archaeological Wood

and the Effects of Mass Tourism

The Case Study of the Vasa Warship

By Cristina Cabello‐Briones

The Use of Ground Penetrating Radar for the Assessment of the

Conservation State of an Historic Building

By Lucian Cristian Ratoiu

Virtual Aesthetic Presentation of Polychrome Sculptures

Preserving the artistic authenticity of polychrome carved wood

pieces in the conservation‐restoration process

By Daniela Cristina Pintilie

EVENTS

8

53

43

28

19

52

27

29

8

27

INDEX

e‐conservation 5

new

s&

view

s#CULTUREMATTERS

A pamphlet the Demos think‐tank

published a few years ago, entitled

‘It's a Material World’ [2], has been

a growing influence upon the con‐

servation community, and recently

IIC published an update from one

of the authors [3]. The stated aim

of these publications was to raise

awareness and champion “in wider

society and politics” [3, p. 242] the

values of heritage conservation.

I particularly appreciated the idea

that conservation has a unique role

within society in that “conservators

provide a paradigm not just for fix‐

ing things when they are broken, but

for a wider social ethos of care, where

we individually and collectively take

responsibility and action” [2, p. 16].

In thinking about this I remembered

a lecturer I had at University who

once said, and I paraphrase, ‘If you

really wanted to save heritage, you’d

go into politics’. At the time this

struck me as an interesting state‐

ment, and looking back it was per‐

haps bizarrely the moment that I

realized I wanted to study conser‐

vation. Sometime later a visiting

lecturer who was associated with

the EZLN [4] lectured to us about

the importance of cultural heritage

to the Maya of Chiapas, Mexico, and

for me the circle was squared. Just

as I realized art, culture, and politics

"Why should the lamp or the house be an art object, but not our life?"

(Michel Foucault, 1984) [1]

By Daniel Cull

are as much about everyday life as they are about

the contents of cases in museums, I also realized

that not all interactions between cultural heritage

and politics take place between white men in the

board rooms of quasi‐governmental heritage or‐

ganizations.

The 'Material World' writings were primarily aimed

at a western audience in response to the current

economic climate in which arts and cultural in‐

stitutions are increasingly being asked to justify

their existence in economic terms. The authors

developed the concept of ‘social capital’ as an

alternative to the economic approach, they con‐

sider conservation as a spectrum of activities from

the highly technical to those that anyone with a

bit of training could do, therefore they call for

an increase in volunteerism, with the logical as‐

sumption that this will lead to communities see‐

ing value in supporting heritage. As the Middle

East is realizing, and this pamphlet noted, “the

social glue that holds communities together is

changing. We are not talking to each other less;

we are talking to each other differently” [5, p. 8].

Many of these changes are coming as a result of

the logic of the emerging social media, the logic

of total access and community control. Although

the authors realize that through this emerging

media we can “help reconnect and facilitate the

formation of new geographic communities" [5,

p. 8], they appear to miss or underplay the poten‐

tial for alternative or hybrid forms of funding.

Although crucially they radically invert Maslovian

principles to state "preservation is not a sign of

decadence, but a sign of wisdom" [5, p. 6].

e‐conservation

The title of the ‘Material World’ pamphlet was in‐

tended as “a bold statement of fact, a reminder of

the role that objects, buildings, and ideas play in

anchoring society” [3, p. 243]. However, I read it

through the prism of the movement within conser‐

vation theory towards the value placed on safe‐

guarding the immaterial and metaphysical, and

recently reconsidered the collection of writings

in light of the events in Egypt in which, during the

popular uprising, risks of looting were noted at

cultural institutions across the country. Whilst

many cultural institutions in the West called for

state intervention to protect objects, the protest‐

ers on the streets had already taken matters into

their own hands and protected the museums, ar‐

chives and cultural sites [6]. In so doing we wit‐

nessed that when people have “an active relation‐

ship with the past” [3, p. 247] they’re not only

willing to volunteer to cut the grass around the

Cerne Giant but they’re willing to risk their lives

for their cultural heritage. Their actions were as

profound a statement on the value of conserva‐

tion to society as I imagine I will ever see. Their

actions suggest that it is not the artifacts them‐

selves that are important, but the relationship

that people have to them, and through them to

each other, that makes them important. As her‐

itage practitioners perhaps our most significant

role then is to help generate and facilitate peoples

'active relationships' with their cultural heritage.

For ultimately it’ll be the people who decide the

future of the past.

Bibliography

[1] M. Foucault, “On the Genealogy of Ethics: An

Overview of Work in Progress”, in The Foucault

Reader, Paul Rabinow (ed.), Pantheon Books,

New York, 1984, p. 236

[2] S. Jones and J. Holden, It's a Material World:

Caring For the Public Realm, Demos, London, 2008,

available at URL [pdf], accessed on February 20,

2011

VIEWS

e‐conservation 7

The NDP building burns next to the Egyptian Museum. Photo by darkroom productions, January 29, 2011. Some rights reserved.

VIEWS

8 e‐conservation

[3] S. Jones, "It’s a Material World", Studies in

Conservation 55(4), 2010, pp. 242‐249

[4] Ejército Zapatista de Liberación Nacional,

available at URL, accessed on February 20, 2011

[5] Anna Somers Cocks interview with Samuel

Jones, Dialogues for the New Century series, IIC

Tanks and soldiers guard the Egyptian Museum. Photo by Nebedaay, January 25, 2011. Some rights reserved.

DANIEL CULLConservatorThe Musical Instrument Museum

Daniel Cull is from the West Country of the British Isles. He trained at the Institute of Archaeology,

University College London, where he received a BSc in Archaeology, MA in Principles of conservation,

and an MSc in Conservation for Archaeology and Museums. He was later awarded an Andrew W. Mellon

Fellowship at the National Museum of the American Indian/Smithsonian Institution, Washington, DC.

He currently works as a conservator at the Musical Instrument Museum and as a collaborator with

e‐conservation magazine.

Website: http://dancull.wordpress.com

Contact: [email protected]

Annual General Meeting, 2010, Sackler Centre,

Victoria and Albert Museum, London, January

28, 2010, available at URL [pdf], accessed on

February 20, 2011

[6] Looting spreads in Egyptian cities, Al Jazeera

English, 29 Jan 2011, available at URL, accessed

on February 20, 2011

Review by Tomasz Kozielec

The international conference “Parchment and

Leather – research, conservation‐restoration,

craft” was organized by the Department of Paper

and Leather Conservation of the Nicolaus Coper‐

nicus University in Toruń, Poland, and took place

on October 21‐23, 2010. The conference was at‐

tended by representatives of institutions from

different countries who also presented lectures

on current conservation‐restoration issues and

modern research techniques. A concert on harp‐

sichord, “At Bach's home” by Ryszard Moroz, as

well as the exhibition “Conservation‐restoration of

gilt leather – students and their adviser” by Halina

Rosa were some of the highlights of this event.

The conference was divided into nine sessions

devoted to broad views of research problems and

questions regarding conservation of historic parch‐

ment and leather artefacts. After the registration,

the opening speech was given by Elżbieta Jabłoń‐

ska, Head of the Department of Paper and Leather

Conservation.

Justyna Król Weronika Liszewska and Zofia Żukow‐

ska, from the Faculty of Conservation‐Restoration

of Old Prints and Graphics, Academy of Fine Arts,

Warsaw Polytechnic (Poland), delivered the first

lecture entitled “Non–destructive analyses of il‐

luminated manuscript on parchment ’Testamentum

Vetus’ from the first half of the 14th century, from

the collection of the Higher Clerical Seminary in

Włocławek”. Besides visual examination of the

decayed areas of illuminations, Laser Induced

Breakdown Spectroscopy (LIBS) and Raman spec‐

troscopy were performed. The results of the ana‐

lysis were determinant for the better planning of

the conservation‐restoration treatments.

The second lecture was given by Agnès Le Gac, from

the Department of Conservation‐Restoration of

October 21‐23, 2010

Toruń, Poland

Organized by:The Department of Paper and Leather Conservation

of the Nicolaus Copernicus University

http://www.zkpis.umk.pl/

PARCHMENT AND LEATHER –RESEARCH, CONSERVATION‐RESTORATION, CRAFT

REVIEWS

e‐conservation 9

Opening speach by Elżbieta Jabłońska, Head of the Depart‐ment of Paper and Leather Conservation.

Exhibition of cordovans.

the New University of Lisbon (Portugal), who pre‐

sented “White leather glue: its reconstitution,

analysis and comparison with both parchment

and rabbit‐skin glues”. The researcher used SEM‐

EDX, originating visual and elemental mapping

images, to analyse white leather, parchment and

samples of glues. This research is important, among

other things, in the study of the rich polychrome

coatings applied on the 17th‐18th century religious

sculptures in Portugal. Closing the first session,

and after a coffee‐break, the participants had the

opportunity to attend the opening of the exhibi‐

tion “Conservation‐restoration of gilt leather –

students and their adviser”.

Afterwards, the lecture on “Biodeterioration of

historic parchment and leather – a summary of

studies in the Department of Paper and Leather

Conservation” given by Joanna Karbowska‐Ber‐

ent, from that same department at the Nicolaus

Copernicus University, opened the second session

and described research carried out on vegetable

and alum tanned leathers and parchments (mainly

from historical objects). Many processes and de‐

gradation stages of the materials caused by dif‐

ferent microorganisms were observed. As seen, one

of the most important factors in stopping biode‐

terioration is the presence of vegetable tannins

which protect the collagen fibbers against decay.

The presentation “Some early examples of sewing

tackets and thonged extensions” by Matthew Hat‐

ton, from the Glucksman Conservation Department

of the Trinity College Library in Dublin (Ireland),

emphasized eclectic problems of fragmented texts

in collections (which were brought together to

form single or multiple volumes) based on the

example of manuscript 1337 “Miscellanea Hiiber‐

nica”. Among the many interesting facts he de‐

scribed, the author presented interesting solutions

of restoration.

The afternoon session started with Marlena Viha‐

kara and Wiebke Findeisen, from the Centre for

10 e‐conservation

A general view of the conference hall.

REVIEWS

Preservation and Digitisation, The National Lib‐

rary of Finland, with their lecture “Conservation

and digitisation of medieval parchment fragments

in the National Library of Finland” in which they

presented the great and large collection of that

Library, and the making of the project “Save the

Book”. This project assumes the digitization, docu‐

mentation and basic conservation treatments.

The lecture on “Technology study and conservation

of thirteen traditional rural shoes of 19th century

from Florina region, northern Greece” was given

by Ekaterini Malea and Anastasia Tampaka, from

the Technological Educational Institute of Athens

(Greece), broadening the knowledge on techno‐

logy of leather shoes from 1900‐1935 from that

region. The authors presented the conservation‐

restoration treatments performed as well as the

subject of a footwear exhibition.

The next lecture, entitled “Parchment scrolls in

the collection of the Jewish Historical Institute –

project of the returning memory. Decoding for‐

bidden meanings” by Violetta Bachur, from the

Jewish Historical Institute in Warsaw (Poland),

introduced the conference participants to the

world of great Jewish art and craft. The different

types of parchments and methods of preparation,

Jewish scrolls, mezuzot, and many other sacred

e‐conservation 11

objects, as well as the Jewish law were presented

in detail. She also indicated the state of preser‐

vation of these objects.

The fourth session started with two lectures on

the history, techniques of making and restoring

cordovans (also called “gilt” or “Spanish leather”).

This session was opened by Ojcumiła Sieradzka‐

Malec, from the Royal Wawel Castle in Cracow (Po‐

land), with the presentation of “Wawel’s cordovans

– the issues’ outline”. The lecture focused on the

decoration history of the Royal Wawel Castle in

Cracow with the description of some technical

aspects.

The next presentation, “Conservation‐restora‐

tion of cordovans – problems and solutions” by

Halina Rosa from the Department of Paper and

Leather Conservation of the Nicolaus Copernicus

University, showed the long history and method

of preparation of cordovans from ancient times.

The oldest written source on gilt leather is the

description of Peder Manson from the 1515. The

main part of her speech was about the state of

preservation and conservation‐restoration prob‐

lems, such as the levelling deformations of cor‐

dovans and the cleaning of the painting layer.

She shared her wide and long experience on this

field with the participants.

REVIEWS

Presentation by Joanna Karbowska‐Berent, Department ofPaper and Leather Conservation, Nicolaus Copernicus Uni‐versity, Toruń, Poland.

Ojcumiła Sieradzka‐Malec from Cracow, Poland, speakingabout problems with gilt leather decorating the Royal WawelCastle.

Grażyna Macander‐Majkowska, also from the Acad‐

emy of Fine Art in Warsaw, approached a very in‐

teresting subject ‐ “Pastel portrait on parchment

– the unique work of art” ‐ certainly convincing

all participants that such great historical objects

are outstanding works of art (i. e. have a specific

technique). The work of artists who were using

the pastel technique reached its apogee in the

18th century. The author discussed two examples

of pastels from the second half of 18th century.

The parchment theme was continued by Katarzyna

Nowak, Anna Rychter and Aleksandra Szalla‐Klee‐

mann, from the Conservation Section of the De‐

partment of Preservation Jagiellonian Library

Collection in Cracow, with the presentation of

“Variety of use of parchment as bookbinding and

writing material in the collection of the Jagiello‐

nian Library”. The authors indicated the use of

this material for bookbinding purposes such as

raised bands, cloth joints or pastedowns, flyleafs,

covers, and for the making of sheets of manuscripts

and prints. They showed that parchment has a

very good durability, permanence, and state of

preservation if stored in proper and stable condi‐

tions of temperature and relative humidity. The

authors also posed questions concerning the dis‐

covery of codex fragments during conservation‐

restoration treatments.

The morning of the second day started with a series

of announcements and short presentations. One

that must be highlighted was dedicated to the

Museum of Literature and Printing in Grębocin, a

museum of writing, printing, paper‐making, and

bookbinding history and technology on the sub‐

urbs of Toruń. The great “pearl” of this region was

presented by its founder and head, Dariusz Subocz

with “The machines and bookbinder devices in the

collection of Literature and Printing Museum in

Grębocin”. Examples of papermaking moulds, book‐

binding and writing tools, composition of old inks,

organized in past museum workshops, giving know‐

ledge on the processing of animal skins into leath‐

er and parchment, and on how to produce paper

by hand, as well as how to print, sew and cover

books, and many others subjects were presented.

“Parchment Torah from Lubaczów – conservation

problems and solutions”, again by Katarzyna Nowak,

was the next interesting lecture. The analysis of

the technique, the state of preservation, causes

of destruction and conservation treatments of

this intensively deteriorated object were presen‐

ted. The use of neodymium magnets for restora‐

tion purposes was one of many other interesting

solutions shown. The theme of museum collection

initiated by Dariusz Subocz was continued by Mo‐

nika Zakroczymska's lecture “The short charac‐

teristics of the collection of Museum in Gdynia”,

from the Museum of City Gdynia (Poland). The

collection of photographs, documents, maps and

plans, posters and diverse material culture items

(such as furniture, home and gardening devices,

clothes, flags, dishes, and decorations) were

presented.

Another enthralling museum collection was pre‐

sented by Ewa Martin‐Sobecka, entitled “Collec‐

tion of leather objects in Ethnographic Museum

in Toruń”. There are almost 60.000 different ob‐

jects in their collection! Haberdashery, furniture

upholstery, small bellows used in beekeeping,

leather hand‐bags and bags, suitcases, spectacle‐

case, holders for knives, razors, cigarette cases,

wallets, purses, briefcases and watch straps and

many other leather objects were showed in the

presentation.

The fifth session was opened with “Conservation‐

Restoration of Nubian Leather Finds from the 11th

Century” by Myriam Krutzsch, from the Egyptian

Museum in Berlin (Germany), Claudia Näser, from

the Humboldt University in Berlin, and Patricia

12 e‐conservation

REVIEWS

Engel, from the European Research Centre for Book

and Paper Conservation‐Restoration in Horn (Aus‐

tria). Specifications and conservation treatments

of 100 fragments of inscribed parchment, numer‐

ous remains of leather bindings with a multitude

of decorative elements and several texts on folded

leather were shown. The presented materials were

especially important for leather conservators be‐

cause little is known about bookbinding in 11th

century Nubia. The authors focused also on the

“Step leather project” and the “Environmental

Leather Projects”.

“Protecting works over the Coptic parchment manu‐

script (the 9th and 10th century) and the specificity

of its destruction” by Anna Thommée, from the

Department of Art, Collection, Books and Docu‐

ments Conservation in Toruń, was an interesting

example of full description of conservation treat‐

ments carried out from “rescue” treatments to the

stage of making of protective wrappers. Three

manuscripts discovered by Polish archaeologists

were in very poor condition. Since 2006, the books

have been preserved in the National Museum Work‐

shop in Alexandria, in a common project of the

Mediterranean Archaeological Centre of Warsaw

University and Polish Workshops of Heritage

Conservation S.A.

Examples of beautiful parchment objects from

the collection of the Museum of Westphalia and

Lippe were presented by Ryszard Moroz, from the

Westphalian State Museum of Art and Cultural

History (LWL) in Münster (Germany) in his lec‐

ture “Open‐work parchment”. The unique tech‐

nique of such outstanding objects (ornamented

parchment by cutting out a variety of patterns

with great precision!) and their conservation

problems were emphasized.

The sixth session started with Sara Mazzarino's

lecture, from the British Library in London (UK),

on the “Humidification and tensioning of parch‐

ment manuscripts ‐ limitations and possibilities of

different method of parchment tensioning during

conservation treatments”. An important question

was raised: “Is it always appropriate to humidify

and tension degraded parchment documents?”.

In the lecture “Problems and questions connected

with the conservation of 15th‐century parchment

codex “Breviarium Vladislaviense”, by Weronika

Liszewska and Jacek Tomaszewski, from the Aca‐

demy of Fine Arts in Warsaw, the authors discussed

its state of preservation, historical, ethical and

aesthetical problems. A modern technique of filling

losses in parchment sheets by using of parchment‐

cellulose pulp mixture was presented along with

the description of the conservation treatments.

However, not only issues concerning the conser‐

vation‐restoration treatments were discussed dur‐

ing the conference. The fact that the documenta‐

tion is a very important “tool” for conservators

convinced Penelope Banou, Ourania Kanakari

and Angeliki Stassinou from the General State

Archives of Greece, to present “Documentation

as a tool to conservation of parchment collections

belonging to the General State Archives, Greece”.

They underlined that “the study of palaeography,

diplomatic elements (typology), technology of

"Conservation‐Restoration of Nubian Leather Finds from the 11th

Century” by Myriam Krutzsch, Claudia Näser and Patricia Engel.

e‐conservation 13

REVIEWS

materials and techniques, etc., were essential to

resolve conservation and preservation issues”,

and showed many interesting examples of solu‐

tions of conservation‐restoration problems.

“Conservation of a Trousseau Chest Coming from

Balkans to Turkey”, by Nil Baydar from Ankara Uni‐

versity (Turkey), was not only a full description of

construction technology but also of the conser‐

vation treatments carried out on this 18th century

object. Achieving a beautiful result was possible

due to a hard and long work (2 years) on seriously

decayed materials ‐ leather, corroded metals and

other.

Izabela Zając, from the Academy of Fine Arts in

Warsaw, started the seventh session with the

presentation of “Leather bindings – traps and

surprises” on which she demonstrated an example

of a valuable book cover which looked like leather

but was really parchment dyed brown. Another

issue discussed was the impossibility of determi‐

nation of fat content (in percentage) of ancient

leather for re‐greasing conservation treatment.

Sometimes some of the treatments which can be

carried out on ancient leather require complex

solutions. Examples are the recovery of the ori‐

ginal size of leather covers as well as the elimina‐

tion of deformations on the book spine.

Malaurie Auliac and Aline Leclercq, from Condé’s

School in Paris (France), raised a discussion about

the conservation of leather bindings with Japa‐

nese tissue”. The authors showed interesting solu‐

tions of the use of Japanese tissue, and results of

questionnaires conducted among conservators.

“The Missal from Kraśnik” (1400) – the chosen

conservation issues” by Jolanta Żuk Orysiak and

Ryszard Orysiak, from Lublin Museum in Lublin

(Poland), was a presentation about the conser‐

vation‐restoration of one of the most precious

“pearls” among the Polish collection of illumi‐

nated medieval manuscripts.

A very important question ‐ “should conservators

remove all visible dirt and anaesthetic remains

from the surface of materials during conserva‐

tion work?” ‐ gained special significance after

the lecture by Aleksandra Szalla–Kleemann, from

the Jagiellonian Library Collection in Cracow,

Anna Żukowska–Zielińska, from the Jagiellonian

University Archive in Cracow, and Joanna Sobczyk,

from the Laboratory of analysis and non‐destruc‐

tive investigations of heritage objects, National

Museum in Cracow, entitled “Banderia Prutenorum

– conservation search query. The authors used

digital imaging to recreate missing illumination

of the manuscript“. The “Banderia Prutenorum”

is a 15th century parchment codex with images

of 56 Teutonic and Prussian flags (some of them

were conquered during the Tannenberg Battle in

July 1410), from the collection of the Jagiellonian

Library. It is a good example of a successful re‐

construction of missed (cut off) parchment sheet

with illumination depicting the “Madonna with

Child”. Reconstruction was possible by digital

analyses of remains of the painting layer (hardly

visible smudges), on the page with the reflection

of Madonna on one side (back side of next illumi‐

nated parchment sheet). The digital analyses al‐

lowed the reconstruction of the outlines of the

“Madonna and Child”. In the end of the lecture, the

authors asked “what would have happened with the

Madonna reflection, if the pages of the manuscript

had been just – as it usually happens – cleaned?”.

After the coffee break and initiating a new session,

the lecture “The conservation and reconstruction

of the leather items which were found during the

archaeological research in Gdańsk” was presented

by Beata Ceynowa, from the Archaeological Mu‐

seum in Gdańsk (Poland). Although the examples

of leather objects from archaeological excavations

14 e‐conservation

REVIEWS

Małgorzata Grupa from the Archaeology Institute, NicolausCopernicus University, Toruń, Poland, speaking about methodsof conservation‐restoration of archaeological leather.

The presentation of conservation of archaeological leatherfrom Gdańsk Historic State Museum by Bartosz Iwaszkiewiczand Halina Rosa.

had a perfect state of preservation (due to the

high humidity with simultaneous absence of air,

among others!) many problems may arise during

their conservation treatments. These problems

are caused by: the separation of particular elements

of single products from bulk of others; financial

aspects – glycerine method of conservation is used

in most cases because it is often the simplest and

the cheapest treatment; reconstruction ‐ as little

intervention as possible.

The previous conservation issue was further de‐

veloped by another archaeologist, Anna Drążkow‐

ska from the Archaeology Institute of Nicolaus Co‐

pernicus University, in “Problems of conservation

and reconstruction of historical shoes” from dif‐

ferent historical periods and found during differ‐

ent excavations and in various environments. It

was emphasized that treatments such as disinfec‐

tion, cleaning and impregnation have a signific‐

ant influence on further reconstruction works. In

turn, Małgorzata Grupa, also from the same In‐

stitute, presented the methods of conservation of

the archaeological leather used in the Archaeolo‐

gical Institute of Nicolaus Copernicus University.

Conservation treatments in the Institute are con‐

ducted since 1983. Recently researchers focused

on the method of leather conservation at low tem‐

peratures by means of a vacuum chamber.

Bartosz Iwaszkiewicz and Halina Rosa, from the

Department of Paper and Leather Conservation

in Toruń, showed in their lecture “Conservation

of archaeological leather from the Historical Mu‐

seum of the City Gdańsk” a variety of archaeolo‐

gical elements that were found and analyses per‐

formed to those objects. They also presented stand‐

ard conservation treatments which are carried out

in the Department. Removal of black iron‐tannin

complexes through ultrasounds bathing in water

solution of EDTA with addition of the Vulpex soap,

re‐tanning with water‐acetone solutions of sumac,

and re‐greasing (van Soest mixture) are only some

examples of treatments they discussed.

On the last day, the eighth session was started by

Ryszard Moroz, from the Westphalian State Mu‐

seum of Art and Cultural History (LWL) in Münster

(Germany), in his lecture “The document case of

Baron von Stein and the gothic chest – the con‐

servation problems with accumulations on the

leather grain” presented an interesting technique

of two famous leather objects of Baron document

case, the outstanding German politician who lived

at the turn of the 18th and 19th centuries, and the

chest which is a museum rarity. The state of pre‐

servation of the objects was poor, one of the em‐

phasised issues being the accumulations on the

leather grain which were visible at naked eye.

e‐conservation 15

REVIEWS

“Conservation of the saddle in the western type

from the collection of the Horsemanship and Hunt‐

ing Museum in Warsaw ‐ the diversity of materials

and resulting conservation problems” by Dorota

Jutrzenka‐Supryn, from the Department of Paper

and Leather Conservation in Toruń, was a review

on techniques of ancient saddles. The author in‐

dicated that the objects forming the big group in

study are not original, but copies pretending to be

historical (especially from the 17th‐18th century).

Her lecture focused on the conservation treatment

of the saddle from the Warsaw Museum.

Finally, the last session was started with a lecture

by Elżbieta Górska‐Wiklo, from the Archive Uni‐

versity of Glasgow (Scotland), who described the

Archive collection which spans from 1304 to the

present. The author focused on the “Blackhouse

Charters”, the collection of parchment documents

dated between 13th and 18th centuries, which were

repacked and prepared for digitisation. It was also

mentioned the student's support within this pro‐

gramme, helping to developed their knowledge on

preventive conservation, methods of securing the

documents as well as on their storage.

Ethical issues in conservation‐restoration were

raised by Małgorzata Pronobis–Gajdzis and Wioleta

Ługowska, from the Department of Paper and

Leather Conservation in Toruń, in their presenta‐

tion “The parchment and the leather in the his‐

toric codices – the ethical issues”. The lecture sup‐

ported by the idea of Ksawery Piwocki's (“that not

only the work of art is important but the acting

of the artists also influences the value of the ob‐

ject”) was concerned on controversial examples

of removing original parts of codices. The authors

concluded that “the restorer must be aware that

there should not be any violations in the historic

quality of the object even if there are some efforts

to improve the aesthetics of the historic item”.

Elżbieta Jabłońska, Małgorzata Pronobis‐Gajdzis

and Jolanta Czuczko, also from the Department of

Paper and Leather Conservation in Toruń, raised

another important issue with their lecture “Copy‐

ing of precious documents and archival books as

good practice in protection during the exposition

and access”. Because of the unique character of

rare, extremely valuable historical objects, there

are cases when exhibiting the originals is impos‐

sible. For this reason, copies of original objects are

made. Examples of copies of rare historical objects

and copies made by students of the Department of

Paper and Leather Conservation were presented.

The large variety of these lectures testifies to the

fact that problems of research, preservation and

Saddle from the collection of the Horsemanship and HuntingMuseum in Warsaw, subject of the presentation by DorotaJutrzenka‐Supryn.

16 e‐conservation

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Presentation „The parchment and the leather in their historiccodices – the ethical issues” by Małgorzata Pronobis‐Gajdzisand Wioletta Ługowska.

methods of conservation‐restoration of parchment

and leather are a significant concern among con‐

servators. There is a wide variety of objects made

of leather and parchment in the world collections

and many of them surprise by their beauty or un‐

usual technique. The significant sensitivity of these

materials to physical, chemical and mechanical

factors motivate conservators to elaborate new

and safe methods for their conservation, and to

ensure stable storage conditions. Although the

conference has presented many interesting case

studies, describing different treatment methods

and analysis techniques, there are still many prob‐

lems that await solution. Another conference, this

time dedicated to the conservation‐restoration

of historic objects, is being planned for the near

future.

Credits: Photos in this review are by the conference

organizers.

FREE

CONSERVATION

RESOURCES

Art Conservation Research

conservationresearch.blogspot.com

TOMASZ KOZIELECConservator

Contact: [email protected]

Tomasz Kozielec is a paper and leather conservator. He

graduated in conservation from the Department of

Paper and Leather Conservation of the Nicolaus Co‐

pernicus University where he now lectures. His re‐

search interests are the history and technology of

cellulosic and proteinaceous materials, modern ana‐

lytical techniques of historical objects, and the ap‐

plication of new materials and methods for conserva‐

tion‐restoration purposes, such as the use of bacterial

cellulose and neodymium magnets, or the mass strength‐

ening of brittle 19th century papers.

REVIEWS

e‐conservation 17

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19e‐conservation

REVIEWS

Between 2004 and 2010, a series of one‐day con‐

ferences, always on Fridays, took place at the Uni‐

versity of Karlsruhe, Germany, in cooperation with

DOCOMOMO and supported by Beton Marketing

Süd, as research initiative of the university. The

topic of the conference was how to preserve and

use cultural heritage buildings of the Modern

Movement which define the face of today in many

European cities. Organiser was architect Alex Dill,

academic counsellor from the Institut für Baugestal‐

tung, Baukonstruktion und Entwerfen 2 (Institute

for Building Configuration, Building Construction

and Projects 2) (2004‐2007), the then head of the

chair of Architecture and Furniture from the Insti‐

tute Projects, Arts and Theory (2007‐2011). Each

conference was accompanied by an exhibition fo‐

cused on heritage of Modernity in the respective

geographic zones, the vernissage of which took

place in the evening. Starting with 2006 when the

German DOCOMOMO committee was redefined, the

days after the conference were reserved for the

meeting of the committee’s German chapter. The

conferences were recognised by the chamber of

architects as continued learning events for pro‐

fessionals, although they were also open to the

general public. The first three conferences focused

on the differences in the approach in Western and

Eastern Europe, having in focus a country from

each. The following conferences focused on one

country each. We attended all conferences, except

for the opening and closing ones.

Russia and Germany

The first conference took place in January 2004

and it focused on the challenges for architecture

SEVEN YEARS DEDICATED TO THE CONSERVATIONOF THE MODERN MOVEMENT HERITAGE

Karlsruhe, Germany, 2004‐2010 | Organised by Dipl. Ing. Alex Dill and DOCOMOMO Germany

Review by Maria Bostenaru Dan

Visit our website

The Conference Series:“Das architektonische Erbe – zum aktuellen Umgang mit den Bauten der Moderne”Architectural Heritage – on the Contemporary Approach to the Buildings of Modernity

Between 2004 and 2010 a series of seven conferences took place in Karlsruhe, Germany, on the conser‐

vation of architectural heritage throughout Europe. Aimed primarily at practicing architects, they were

organised by Dipl. Ing. Alex Dill, from the Faculty of Architecture, University of Karlsruhe, together with

DOCOMOMO (International Committee for DOcumentation and COnservation of buildings, sites and

neighbourhoods of the MOdern MOvement) and Beton Marketing Süd. It was also the framework in which

the German chapter of DOCOMOMO was re‐launched in 2006 and a declaration adopted. The countries in

focus were Germany, Russia, the Netherlands, Italy, Czech Republic, France, Sweden/Scandinavia and Great

Britain. The opening and closing conferences focused on Russia, for which lessons should be learned from

the functioning practice in conservation in Western and Central Europe. Outreach activities were accom‐

panying exhibitions, books releases, meetings of the DOCOMOMO chapter, and related conferences. In 2011

the series will be discontinued, being replaced by a conference on architecture theory: “Authenticity”.

of Modernity in Russia and Germany in a compar‐

ative approach. The approach was, as the confer‐

ence proved, fundamentally different – the pre‐

servation practices from the West did not reach

Russia and the buildings of the Russian construc‐

tivists, which are of fundamental importance for

the history of architecture, were first documented

and preserved in form of study models. It was also

an occasion to compare the different terms of

Avant‐garde, Modernism and Modernity. At the

time the buildings were erected, there were more

common features in the new practice than today

in conservation. Of use for the conference was the

cooperation between the University of Karlsruhe

and Russian specialists, some of which were visit‐

ing scientists in Karslruhe for several years, such

as Dr. Sergej Fedorov, also co‐organiser of the

conference. The conference was advertised on

the German internet portal of construction news

BauNetz. It was accompanied by an exhibition on

architecture models of the Russian Avant‐garde,

a cooperation project of the students from Karls‐

ruhe and of the University of Stuttgart. The con‐

ference took place on the last day of the exhibi‐

20 e‐conservation

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tion. Among the subjects approached were Russi‐

an Constructivist buildings from St. Petersburg and

Moscow, the house Schminke in Löbau [1] (figure

1) and the preservation and maintenance of Béton

brut (Sichtbeton). Later on, Rüdiger Kramm pub‐

lished a book on this topic [2], as accompanying

publication of the conference series.

The Netherlands and Russia

The second conference took place in October 2004

on the subject of the architecture from the Nether‐

lands, with some contributions about Russia and

Germany (Rettung vor dem Zerfall. Tagung an der

Fakultät für Architektur zur Erhaltung moderner

Bauten). Continuing the intentions of the first con‐

ference to facilitate the exchange and encourage

the preservation of the buildings of the Modern

Movement all over Europe, a delegation of the Mos‐

cow Institute of Architecture took part in the con‐

ference. The chair of the working group on Tech‐

nology of DOCOMOMO, Wessel de Jonge, presented

the restoration of the Sanatorium Zonnestraal in

Hilversum (the Netherlands; figure 2). From the

interesting problematic regarding the restoration

of the sanatorium, we can mention the replace‐

ment of the windows that had to be made out of

a special glass in order to reflect similarly, so the

Figure 1 (left). House Schminke, Löbau (Germany), architectHans Scharoun (1932‐33). Photo by Wojtek Gurak, Somerights reserved.Figure 2 (below). Sanatorium Zonnestraal, Hilversum (theNetherlands), architects Jan Duiker, Bernard Bijvoet andJan Gerko Wiebenga (1928). Photo by Pimvantend, Somerights reserved.

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21e‐conservation

sand to produce them sufficiently transparent

even in double glazing was imported from the

Baltic states. There was also a presentation of

the dean of the faculty Prof. Matthias Pfeifer on

structural restoration of buildings in Germany.

The corresponding exhibition displayed the work

of Konrad Wachsmann, a German architect who

immigrated to the US and was a pioneer of the

prefabricated construction. The University of

Karlsruhe has a database on German architects

who were active outside Germany (Architekten

im Exil 1933‐1945).

Italy (and Czech Republic)

The third conference took place in January 2006

and it focused on Italy, with Eastern/Central Europe

presentations about the Czech Republic. It was the

year when DOCOMOMO Germany was newly defined,

occasion to have the vice‐chair of DOCOMOMO in‐

ternational, Prof. Maristella Casciato, among the

speakers. Maristella Casciato gave an overview

talk on the research and practice of restoration

in Italy. It was followed by two case studies:

‐ the case of “Lingotto”, a hierarchical model, by

Christiana Chiorino from the Polytechnic University

of Turin. The author conducted research on the

preservation of Pier Luigi Nervi buildings in the

context of the XX Olympic Winter Games held in

Turin in 2006, focusing on the approach of rein‐

forced concrete and defining some criteria on

which buildings should be preserved for their

structural characteristics [3, 4];

‐ the case of “Ivrea”, a dynamic model, by Enrico

Giacopelli. Recent efforts of the presenter, together

with Patrizia Bonifazio, are taking place to include

the city of Ivrea on the UNESCO World Heritage List

[5‐7]. For this purpose, International Summer

Schools focused on the architecture and urbanism

are being organised. An open sky museum of mod‐

ern architecture (Museo a cielo aperto dell'Archi‐

tettura Moderna di Ivrea) exists in Ivrea since 2001

to promote cultural tourism for the valuation of

this heritage.

After the lunch break, two case studies from the

Czech Republic were presented: the Villa Müller in

Prague, by Petr Urlich from the Czech Technical

University, about research and practice of the

restoration; and Villa Tugendhat in Brno (figure

3, on which two presentations were given. The

first was by Iveta Cerná about the history of the

building and the other by Prof. Ivo Hammer from

the University of Applied Sciences and Arts (HAWK)

at Hildesheim / Vienna, whose research is dedic‐

ated to the “materiality” of surfaces built of ma‐

terials of the Modern Movement, such as steel and

glass.

In October 2005, before the conference, a team

of photographers from the Institut für Baugestal‐

tung, Baukonstruktion und Entwerfen 2 visited the

Villa Tugendhat, and an exhibition accompanied

the conference. Later, a photo documentation of

the Villa was published [8]. Three years later, in

June 2008, a further DOCOMOMO conference and

a chapter members meeting were organised exactly

at the Villa Tugendhat (minutes are available on‐

line), accompanied by the Declaration of Brno.

Figure 3. Villa Tugendhat, Brno (Czech Republic), architectLudwig Mies van der Rohe (1928‐39). Photo by Mr. Hyde, 2006.

REVIEWS

22 e‐conservation

France

The fourth conference took place in January 2007

and focused on the French architecture. It was

organised in cooperation with the Centre Culturel

Français at Karlsruhe, Germany. The overview talk

was given by Christiane Schmuckle‐Mollard, Chief‐

Architect at Historic Monuments, Paris. After a

discussion about Le Corbusier buildings listed as

UNESCO World Heritage by Michel Richard from

the Le Corbusier Foundation in Paris, case study

presentations followed. The Maison La Roche

(figure 4), where the foundation Le Corbusier is

situated, was renovated afterwards, in 2009, as

we had the occasion to learn during our visit. More

case studies were presented after the lunch break,

such as La Maison de Verre, Paris (1932, architect

Pierre Chareau), by Bertrand Bauchet. Chareau

was an architect whose interiors are characterized

by flexible partitions between the rooms ‐ sliding

walls and similar. Maison de Verre (The Glass House,

figure 5) is called this way due to its facade made

entirely of glass tiles [9]; Other case studies were

La Villa Cavroix in Croix (1932, architect Robert

Mallet‐Stevens), by Prof. Richard Klein, Lille; La

Villa E‐1027 in Roquebrune (1929, architects Eileen

Gray and Jean Badovici), by Prof. Rainer Franke,

Karlsruhe; Cité de La Muette – a vertical garden

city (1934, architect Marcel Lods), by Prof. Pieter

Uyttenhove from Ghent, Belgium, Le Havre and

Auguste Perret, by Prof. Joseph Abram, Nancy,

Paris.

There were also talks on Germany, such as the in‐

troductory one by Rüdiger Kramm on the approach

of the Modern Movement architecture today, de‐

tailing the diminishing acceptance for buildings

of the 1960s and the return to traditional housing

such as Fachwerk.

The conference was accompanied by an exhibition

about the city of ROYAN, a “ville nouvelle” of the

reconstruction 1947‐1959, photographs by Dirk

Altenkirch, Karlsruhe, a city built entirely after the

Second World War. This was the only conference

after which a publication was issued, containing

papers of the presentations in the original lan‐

guage, respectively German, English or French

[10]. In the meeting of the German chapter of

DOCOMOMO a “Declaration of Karlsruhe” was re‐

leased and can be consulted online.

Sweden (and Scandinavia)

The fifth conference took place in January 2008,

and it was focused on Sweden. This was also ad‐

vertised in BauNetz. The introductory speech

about the situation in Scandinavia was given by

Ola Wedebrunn, co‐chair of the DOCOMOMO Inter‐

Figure 4. Maison La Roche, Paris, France, architect Le Corbusier(1923). Photo by M. Bostenaru, 2010.

Figure 5. Maison de Verre, Paris (France), architect PierreChareau (1928‐31). Photo by Subrealistsandu, 2009, Somerights reserved.

REVIEWS

e‐conservation 23

national Technology working group from Copen‐

hagen. A second introductory talk was about the

20th century heritage in Sweden. These were fol‐

lowed by case studies such as The Upper School

for Girls, by Torbjörn Almqvist, from Stockholm,

The Civic Hall from Eslöv, by Mats Edström, who

also wrote a book on this subject [11], Siedlung

Vällingby, by Sven Lorentzi from Stockholm, and

The Town Hall in Göteborg, by Claes Caldenby,

among other not so extensively presented case

studies.

The accompanying exhibition was entitled “Bel‐

levue ‐ MOMONECO” focusing on the Bellevue, a

seaside resort in Denmark, and documented in

the frame of the European project MOMONECO,

“MOdern MOvement NEighbourhood Cooperation,

modernist dreams ‐ 4 case studies” funded through

the CULTURA 2000 European scheme. In the pro‐

ject there were 4 sites involved: Sunila in Finland,

Bellevue‐Bellavista in Denmark, Bat'ovany‐Par‐

tizánske in Slovakia and Ivrea in Italy. Except for

Bellevue, the other three were industrial sites.

The Bellevue resort was designed by the archi‐

tect Arne Jacobsen in the 1930s.

Great Britain

The sixth conference took place in January 2009

and it focused on Great Britain. Immediately after

the introduction, the president of DOCOMOMO

Great Britain and the editor of the extracts from

DOCOMOMO registries [12], Dennis Sharp, spoke

about the Modern Movement in Great Britain.

Overviews were presented by Keyvan Lankarani,

from Avanti Architects, London, Igea Troiani from

the University of Oxford and Alan Powers from

the University of Greenwich. These alternated

with presentations of case study as follows: the

architecture of Ernő Goldfinger, an Hungarian

immigrant less known outside Great Britain and

whose centenary took place recently, by James

Dunnet, from JD Architects, London; the restor‐

ation project of the De La Warr Pavilion (arch. Erich

Mendelsohn and Serge Chermayeff, figure 6), by

John McAslan from JMA Architects, London, a

project which was also the subject of a book [13];

and the Flat Roof House, 1934 (arch. C. Lucas),

by Yasmin Shariff from DS Architects, Hertford.

The last case study presented was about the Zeche

Zollverein Coal Mine Industrial Complex in Ger‐

many, listed as UNESCO World Heritage and an

example to be followed in the conversion of in‐

dustrial architecture through the IBA Emscher

Park project in Ruhr (European Capital of Culture

in 2010).

From the many presentations, one of the most

interesting was a peripheral Modern small scale

building that was a victim of speculation and was

demolished in order to use the property for a

higher building, which unfortunately could not

be avoided. However, the property was classified

as “green belt”, of obviously lower value than the

Modernist building. We could learn lessons from

this for other countries, such as Romania, where

recently, at the end of 2009, a low‐rise building

by interwar architect Henrietta Delavrancea Gibory

was demolished for similar reasons.

Figure 6. De la Warr Pavilion, Bexhill on Sea (UK), architectsEric Mendelsohn and Serge Chermayeff (1935). Photo byMarta Gutowska, 2006, Some rights reserved.

24

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e‐conservation

Another interesting talk was the presentation of

the Twentieth Century Society (C20 Society),

which seems to take over in Great Britain many

of DOCOMOMO's attributes.

The conference was followed by the vernissage

of two exhibitions, one in the well established

tradition regarding the architectural potential

of modern architecture by DOCOMOMO Great Bri‐

tain called “British Case Studies” (figure 7) and

the other regarding the prize of the Wüstenrot

Stiftung foundation from Germany concerning

projects in context (figure 8).

Russia (and Germany)

The seventh and last conference took place in

January 2010 and, like the first one from the

series, was focused on Russia and Germany. The

overview talk was given by Natalia Dushkina about

the Modern Movement Heritage in Russia. The

presented case studies from Russia were the Stu‐

dents Commune House (Arch. Nicolaev), project

and realization, by Vsevolod Kulish, Moscow, and

the Haus Narkomfin (Arch. Ginzburg), a project

by Alexey Ginzburg, Moscow.

In between the presentations on the two coun‐

tries there was an interesting overview on the

situation in Ukraine by Alexander Bouryak, from

Kharkiv (Ukraine).

The case studies presented from Germany were:

the Umspannwerk Berlin‐Scharnhorst, by Paul Kahl‐

feld, Berlin; the ADBG Schule Bernau (Arch. H.

Meyer), by Franz Jaschke, Berlin; and the Fagus

Werk (Arch. W. Gropius and A. Meyer), by Ulrich

Pagels, from Hannover.

The results of student studies were also presented,

such as the Avant‐Garde Heritage workshop in

St. Petersburg by Diana Zitzmann, and Alex Dill,

as well as the report from the excursion Magni‐

togorsk ‐ Ernst Mays buildings today by Thomas

Flierl, Berlin.

The exhibition was called “Avant‐Garde ‐ Defama‐

tion – World Cultural Heritage” and showed a con‐

trast between the approaches in the East and the

West, Russia and Germany.

Conclusions

In 2011, instead of the eighth conference from the

series, the organizers were planning, together with

the annual meeting of the DOCOMOMO chapter

Figure 7. Image of the exhibition hall in the main building ofthe architecture faculty, exhibition about “British Case Studies”,Photo by M. Bostenaru, 2009.

Figure 8. Image of the exhibition hall in the building “Kollegium‐gebäude am Ehrenhof”, exhibition “Gestaltungspreis derWüstenrot Stiftung”. Photo by M. Bostenaru, 2009.

25

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e‐conservation

in Germany, a conference on architecture theory

entitled “Authenticity” that took place on the

28th of January 2011, in the same tradition as the

previous meetings. However, this conference was

not accompanied by an exhibition, a loss that adds

to the lack of related field trips.

The conferences we participated in were extremely

instructive, covering a wide range of countries

and presenting detailed case studies. The exhi‐

bitions provided a welcomed enrichment of these

meetings and were also useful for networking.

We somehow feel sorry that there were not more

books published to document these conferences

and that the only one documenting the presen‐

tations is not available online. The speakers were

great names in heritage conservation and many

of them are published authors with books on the

restoration projects they presented at the con‐

ference, although sometimes the objects were

the subject of books by other authors. Literature

on conservation of the Modern Movement build‐

ings (figure 9) is generally rare once approaches

are also new. Some time ago these buildings were

still considered not old enough to be part of the

heritage. This was also the reason of the creation

of DOCOMOMO, but still the documentation of the

history of architecture is better represented than

conservation issues in the work of the association

in our opinion. Of course the conference could not

cover all relevant buildings even of the covered

countries and obviously cannot replace the study

trips to see the restored buildings. Perhaps the

future conferences could be held at various loc‐

ations in order to allow in situ visits.

Acknowledgments

We gratefully acknowledge the support of the

Marie Curie Intra‐European Fellowship for the

project CA'REDIVIVUS "Preservation of historic

reinforced concrete housing buildings across

References

[1] B. Burkhard (ed.), Scharoun ‐ Haus Schminke: DieGeschichte einer Instandsetzung, Karl Krämer Verlag,Stuttgart, 2002

[2] R. Kramm and T. Schalk, Sichtbeton, Betrachtungen,Verlag Bau und Technik, Düsseldorf, 2007

[3] S. Pace, M. Rosso, and C. Chiorino, Italia 61: TheNation on Show, Umberto Allemande, Torino, 2006

[4] C. Chiorino, “Structural concrete architecturalheritage, problems and strategies for documentationand conservation. The case study of Turin”, in Proceed‐ings of the 2nd International fib Congress, Naples, 5‐8June 2006, 2006

[5] E. Giacopelli and P. Bonifazio (eds.), Il territoriofuturo. Letture e norme per il patrimonio dell’ archi‐tettura moderna di Ivrea, Umberto Allemandi & C. Edi‐tore, Torino, 2007

[6] P. Bonifazio and E. Giacopelli, Olivetti/Ivrea.

Europe" and of the Marie Curie Reintegration

Grant for the project PIANO "The innovation in

the plan of the current floor: Zoning in blocks of

flats for the middle class in the first half of the

20th century", which helped us to attend the

conferences in 2006‐2009.

Figure 9. Books related to conservation of the heritage ofModern Architecture in Germany, mainly the series Baudenk‐male der Moderne. Photo by M. Bostenaru, 2009.

The News section is publishing diverse

information on cultural heritage topics, such

as on‐site conservation projects reports,

conferences, lectures, talks or workshops

reviews, but also course reviews and any other

kind of appropriate announcements. If you are

involved in interesting projects and you want

to share your experience with everybody else,

please send us your news or announcements.

For more details, such as deadlines and

publication guidelines, please visit

www.e‐conservationline.com

REVIEWS

26 e‐conservation

Cultura di fabbrica e cultura architettonica, EditoreMondadori – Electa, 2010

[7] P. Bonifazio and E. Giacopelli, Ivrea, passato efuturo di una company town, Parametro 262, AnnoXXXVI Marzo/Aprile, 2006

[8] A. Dill, R. Kramm and I. Cerna with C. Engel, T.Mechau and B. Seeland, Vila Tugendhat Brno, Was‐muth, 2008

[9] P. Chareau and B.B. Taylor, Pierre Chareau. De‐signer and Architect, Taschen Verlag, 1998

[10] R. Kramm (ed.), Zum aktuellen Umgang mit denBauten der Moderne: Frankreich, Universität Karlsruhe,Fakultät für Architektur, Institut für Baugestaltung,Baukonstruktion und Entwerfen, Karlsruhe, 2007

[11] M. Edström, Medborgarhuset i Eslöv ‐ Eslöv CivicHall, Arkitektur Förlag, 2007

[12] D. Sharp and C. Cooke, The Modern Movementin Architecture – Selections from the DOCOMOMO re‐gisters, 010 Publishers, Rotterdam, 2000

[13] A. Fairley, De La Warr Pavilion: The ModernistMasterpiece, Merrell Publishers Ltd, 2006

MARIA BOSTENARU DANArchitectural Engineer

Maria Bostenaru Dan (Dipl.‐Ing.) has an engineer‐

ing degree in architecture, specialisation in ur‐

banism, from the Universität Karlsruhe, Germany

(1999). She specialised in the study of risks on

built heritage, seismic retrofit, doing research in

Karlsruhe (Germany), Pavia (Italy) and Bucharest

(Romania).

http://www.googleartproject.com/

GOOGLE ART PROJECT

Google’s last tool has surprised not only art lovers

among the general public but also art historians

and conservators. “Google Art Project” is a direct

and interactive way for anyone to visit one of 17

major art museums in 9 countries for free, without

leaving the comfort of their home. Up to this point,

the museums that have collaborated in this pro‐

ject and agreed to exhibit their galleries online

are Altes Nationalgalerie, The Freer Gallery of Art

Smithsonian, National Gallery (London), The Frick

Collection, Gemäldegalerie, The Metropolitan Mu‐

seum of Art, MoMA, Museo Reina Sofia, Museo

Thyseen – Bornemisza, Museum Kampa, Palace of

Versailles, Rijksmuseum, The State Hermitage Mu‐

seum, State Tretyakov Gallery, Tate, Uffizi and Van

Gogh Museum.

One of the finest features of this project is that

not only it enables the visitor to “walk” through

the museum rooms, in a 360º view, but it also al‐

lows visualising the artworks at incredible zoom

levels. This project promotes easy access to art

but moreover, it offers an important tool for the

study of technical aspects of artworks, a tool that

will prove useful to scholars, teachers, research‐

ers, conservators and many other professionals.

The idea started as part of the “20% project”, the

time that Google allows its engineers to work on

their own initiatives. The Art Project is powered by

their Street View technology and after 18 months

in the making, it the includes 385 gallery rooms

with more than a thousand high‐resolution images

by 486 artists. From these, there are 17 pictures ‐

one from each museum ‐ that are available at su‐

"Explore museums from around the world, discover and view hundreds ofartworks at incredible zoom levels, and even create and share your owncollection of masterpieces"

per‐high resolution, among which "The bedroom"

and "The Starry Night" by Vincent van Gogh,

"In the Conservatory" by Edouard Manet, "The

Nightwatch" and "Return of the Prodigal Son" by

Rembrandt Harmensz van Rijn, to name just a few.

These images are scans with over one gigapixel

in size (over 1 billion pixels), the largest having

more than 12 gigapixels. This introduces a whole

new experience for the viewer who has never had

the possibility to analyse such close ups. As a curi‐

osity, but perhaps deliberate, the painting chosen

for scanning from the National Gallery is "The Am‐

bassadors" by Hans Holbein the Younger (1533).

This painting is world famous by its anamorphic

perspective. It includes a distorted skull that the

viewer can only see correctly while standing in a

certain angle at the right side of the painting.

Of course that nothing can substitute one’s visit

to the museum and the real life experience, but

we must appreciate this great initiative of mu‐

seums to allow us to be a virtual visitor in their

galleries whenever we want.

NEWS

27e‐conservation

THE ORTHODOX CHRISTIAN SAKKOSEcclesiastical Garments Dating from the 15th to the 20th Centuriesfrom the Holy Mountain of Athos

Collection Survey, Scientific Analysis and Preventive Conservation

The sakkos, traditional vestments worn by bishops

of the Orthodox Church, are the object of study

of a recent publication authored by Dr. Christos

Karydis, specialist in textile conservation. The book

is the result of the research of the Euro‐Mediter‐

ranean post‐Byzantine ecclesiastical garments

collection from the Mount Athos, Greece, the most

important monastic centre of the Orthodoxy.

The study includes an overall of 52 sakkoi from 14

monasteries, dating from the 15th to the 20th cen‐

tury, which had never been studied before. The

book offers one of the widest and most complete

views on the sakkoi, from their cultural and historic

significance to their material, stylistic analysis

and conservation state assessment. The import‐

ance of this book is even greater due to the lack

of published literature dedicated to this subject.

The garments were systematically studied by ana‐

lytical techniques, namely Optical Microscopy, HPLC

and SEM‐EDS, for the characterization of different

materials such as fibres, dyes and metal threads,

and for the identification of their degradation

sources. The conservation of this collection is a

major concern for the author who introduced a

new preventive conservation approach for the

care of the collection: the study begins with a dis‐

cussion of the nomenclature, while it addresses the

issue prevalent in Byzantine and post‐Byzantine

research, as to the historical provenance of this

liturgical garment. Different approaches ranging

from art historic and semiotic research to scientific

examination using sophisticated analytical tech‐

niques are applied, in order to introduce a cultural,

historical and technological context of the garments.

Dr. Christos Karydis is researcher and lecturer in

preventive conservation and history of ecclesi‐

astical textiles. He was involved in the protection

of textiles collections from Mount Athos, Jerus‐

alem, Constantinople, Colombia, Spain, UK and

Greece. He is the author of the first book written

in Greek on the preventive conservation of textiles.

The recently published “The Orthodox Christian

Sakkos” is a systematic study of great value not

only to scholars but also to textile conservators

and other museum professionals.

Author: Christos Karydis

Publisher: Archaeopress

Pages: 410 pages with CD‐Rom

Publication date: 2010

ISBN: 9781407307169

Language: English

NEWS

28 e‐conservation

even

ts

The events in this section are linked to the

original homepage of the organisers or to the

calendar of events at www.conservationevents.com.

Click on "Read more..." to find out more details

about each event.

Tools for Prioritizing CollectionCare Print

Date: March 22 Read more...

Place: Birmingham, UK

In all organisations, and especially in cash‐

straitened times, priorities in collection care

have to be established. Organisations have to

choose what is most important to protect and

make available to use and choose which pre‐

servation actions will most effectively achieve

their aim of long‐term access to collections in

libraries and archives. This event looks at a

selection of tools used to establish the prio‐

rities in collection care allowing participants

to consider how the tools could be used in

their own organisations.

Back to the Roots: Workshop onthe Preparation of HistoricalLake Pigments

Date: March 23‐25 Read more...

Place: Munchen, Germany

The workshop is aimed to promote a better un‐

derstanding of the nature, preparation and use

of historical lake pigments, which were relevant

for painting and polychromy. The training will

be targeted at conservator‐restorers, scientists

and art historians who have a special interest

in artist materials, and who wish to deepen

their theoretical and practical knowledge of

the traditional preparation of pigments made

from natural dyestuffs.

Apri

l201

1

1st SAA Symposium

Date: March 30 ‐ April 3 Read more...

Place: Sacramento, California, USA

The Symposium focuses on recent, international advances

in the use of pXRF and other portable, field technologies

for archaeochemical studies of sites in the Americas.

Below the surface of every landscape is chemical evidence

of past human activity and, potentially, an historic site.

Recent advances in the use of portable X‐Ray Fluores‐

cence (pXRF), RAMAN technologies and the reduction in

costs for laboratory analyses have made these technolo‐

gies affordable for field studies that "complete the circle

of understanding" of historic era terrestrial and marine

sites through the integration of archaeochemistry, Ar‐

chaeogeophysics, literature research, oral interviews

and excavation.

Mar

ch20

11

Museums and the Web 2011 (MW2011)The international conference for cultureand heritage on‐line

Date: April 6‐9 Read more...

Place: Philadelphia, Pennsylvania, USA

Museums and the Web is an annual conference exploring

the social, cultural, design, technological, economic, and

organizational issues of culture, science and heritage

on‐line. Taking an international perspective, MW reviews

and analyzes the issues and impacts of networked cultural,

natural and scientific heritage – wherever the network

may reach. The MW community has been meeting since

1997, imagining, tracking, analyzing, and influencing

the role museums play on the Web, and having fun doing

it. MW Program features plenary sessions, parallel ses‐

sions, un‐conference sessions, museum project demon‐

strations, commercial exhibits, mini‐workshops, profes‐

sional forums, two design 'Crit Rooms', and the Best of

the Web awards.

e‐conservation

ART '11: 10th International Conference onNon‐destructive Investigations and Micro‐analysis for the Diagnostics and Conservationof Cultural and Environmental Heritage

Date: April 13‐15 Read more...

Place: Florence, Italy

Non destructive analysis has proved to be the gold stand‐

ard to achieve more successful and long‐lasting preser‐

vation. Many non‐destructive techniques and evaluation

methods applied in the natural sciences offer advantages

to cultural heritage preservation. The synergy between

experts will lead to the continuous development and

adjustments of new scientific methods and their applic‐

ation in the fields of preservation, reconstruction and

diagnostics of museum and archeological objects. The

conference will bring together, in one or the world art

capitals, conservation scientists, curators, art histori‐

ans, architectural researchers and experts in non‐de‐

structive evaluation and material analysis.

Wall Paintings Exposed to OutdoorWeathering

A Conservation Challenge at the World Heritage

Site Constantine Basilica in Trier

Date: April 7‐9 Read more...

Place: Trier, Germany

Using the example of the Constantine Basilica in Trier,

this conference wishes to present the current research

results in order to compile the various difficulties in

preserving outdoor wall paintings. This will be followed

by presentations of other significant case studies and

possible conservation solutions. On the second day, the

major focus will be future methods of in‐situ conserva‐

tion and the conveying of contents, while taking into

consideration potentially conflicting interests of tourism,

monument conservation and art science. The conference

language is German (with translated abstracts).

Apri

l201

1EVENTS

Apri

l201

1

The Science of Objects and Collections

The British Library Conservation ResearchConference 2011

Date: April 11 Read more...

Place: London, UK

This one day conference will explore two linked themes:

understanding the nature of objects, and understanding

the nature of collections. What can we learn about the

behaviour of whole collections by studying individual

objects, and what can we learn about individual objects

by studying whole collections? Topics to be covered in‐

clude the use of spectroscopy and multi‐spectral imaging

to reveal more about the nature of objects, statistical

methods for understanding the nature of collections,

and the influences of the environment on collections.

The full programme is available from the organiser's

website.

Non‐destructive and Microanalytical

Techniques in Art and Cultural Heritage

Date: April 26‐29 Read more...

Place: Berlin, Germany

The aim of TECHNART 2011 is to provide a scientific forum

to present and promote the use of analytical spectroscopy

techniques in the field of cultural heritage. The confer‐

ence builds on the momentum of TECHNART 2009 offering

an outstanding and unique opportunity for exchanging

knowledge on leading edge developments. Cultural herit‐

age studies are interpreted in a broad sense, including

pigments, stones, metals, glass, ceramics, chemometrics

on artwork studies, resins, fibers, forensic applications

in art history, archaeology and conservation science.

The preliminary program will soon be available from the

organiser's website.

30 e‐conservation

arti

cles

AREAS OF PUBLISHING

Conservation TreatmentMural Painting

Painting

Stone

Sculpture

Textiles

Paper / Documents

Photography

Metals

Tile / Ceramic / Glass

Furniture

Music instruments

Ethnographic assets

Archeological objects

Conservation ScienceScientific research

Material studies and characterisation

Analytical techniques

Technology development

Biodeterioration

State‐of‐the‐art

Reviews

Preventive ConservationTheoretic principles

Case studies

Documentation in ConservationStandardisation

Documentation methods

Data management

Conservation TheoryEthics

Conservation History

Art History, Iconography,

Iconology, Chemistry, Physics,

Biology, Photography, Cultural

Management, Museology,

Computer Science, Legislation and

Juridical Processes, Conservation

Policies

and any other field applied to

Conservation and Restoration

of works of art.

Find out more: www.e‐conservationline.com

e‐conservation

INFRARED REFLECTOGRAPHY USING3D LASER SCANNING

By Christian Dietz, Gianluca Catanzaritiand Alfredo Jimeno Martínez

Introduction

Infrared radiation is situated within the electro‐

magnetic spectrum just past the red segment of

visible light and before the microwave region.

Generally, the IR spectrum is divided into IR‐A

(700‐1400 nm, near‐infrared), IR‐B (1400‐3000

nm) and IR‐C (3000 nm ‐ 1 mm). Unlike visible

light, infrared radiation penetrates somewhat in‐

to the layers of a painting, depending upon the

pigments, varnishes and other materials used

during its execution. Backscattered light therefore

contains information about deeper paint layers,

underdrawings and canvas state. In particular,

making visible the compositional sketches, nor‐

mally done using charcoal and applied on the pre‐

paration layer prior to the use of paint, but also

signatures, dates, inscriptions or monograms hid‐

den underneath the painted surface layer, provides

to the professional valuable information that can

help to assign authorship, track back the creational

process and detect changes in the painter's ori‐

ginal intentions (known as "pentimenti") [1].

The first attempts to exploit this technique for

art and restoration purposes began in the 1930s,

when suitable film material became commercially

available. Infrared photography was limited to the

real near‐infrared, a range approximately between

700 nm and 900 nm. Modern infrared reflectography

(IRR), a commonly used and non‐destructive tech‐

nique for the investigation of ancient paintings,

makes use of digital cameras, whose incorporated

CCD sensors are inherently sensitive to infrared

light, in that way images with a wavelength from

800 nm to 2000 nm may be obtained [2].

The instrumental setup of an investigation em‐

ploying IRR is depicted in figure 1.

The best contrast is obtained when opaque pig‐

ments that are transparent for the infrared light,

such as lead white, have been used in the painting.

In this case, the infrared radiation passes through

the pictorial film until it hits either a black carbon

pigment of the underdrawing, where it is absorbed,

or the adjacent ground layer, often made of white

33e‐conservation

SCIENCE AND RESTORATION AT THE SERVICE OF INTERPRETATION

A 3D laser scanning instrument, equipped with an optical transmitter containing a continuous 785 nm

diode laser, was used in order to obtain infrared reflectography data of oil paintings. The investigation

was carried out in two modern oil and acrylic paintings on canvas and a late 16th century panel painting.

In the first case results were compared with existing documentation of the artistic process and in the

second with a previously elaborated study by IR reflectography. Data recording took as short as five

minutes, providing an IR image comparable to those obtained by reflectography in the IR‐A zone of the

spectrum. The technique additionally provides high resolution topographic data of the artworks’ sur‐

rounding, such as frame and adjacent walls, and has potential to be developed into an alternative

method for investigation of pigment layers on virtually any surface, especially if these are of great

dimensions or almost inaccessible.

Figure 1. A typical instrumental setup for IR reflectography.The red lines indicate infrared (IR) while the black linesindicate visible radiation (VIS).

gesso (calcium sulphate), where it is backscattered.

The result is a picture of black areas (absorbed

light) over white background (reflected light).

IRR is nowadays widely accepted and used as a

valuable tool for the investigation of drawing con‐

stituents [3], but can also be applied to obtain

information on pigments on supports other than

canvas or wood, such as mural [4] and cave paint‐

ings [5]. Often, IRR recordings are overlaid to vis‐

ible (VIS) measurements to produce false colour

infrared composites, normally generated by plot‐

ting the green parts of an image as blue, the red

parts as green and the near‐infrared data as red,

providing additional information on pigments, var‐

nishes and binding media. Recent developments

tend to use integrated approaches, such as com‐

bining data obtained by IRR with thermography

[6], X‐ray fluorescence or colourimetry [7].

A main drawback of IRR is the time consumption

necessary for manually mounting many mosaic

pictures, using dedicated software. This is partic‐

ularly true for paintings of great dimension, where

scaffolding has to be constructed for the investi‐

gation in situ, because the camera has to be posi‐

tioned relatively close to the artwork. Accurate x‐y

translation of the painting on a plane perpendicu‐

lar to the camera is also difficult due to geometrical

and photometric distortions. Finally, a uniform

illumination by the lamps is also not always easy

to achieve.

A wide range of laser techniques are nowadays

commonly used for heritage applications [8]. Upon

the laser power applied, they may be divided in

three categories: (a) high power applications that

may be considered somewhat destructive, normally

using Nd:YAG lasers, such as laser ablation for

diagnostic [9], cleaning purposes [10] or laser‐

induced breakdown spectroscopy [11]; (b) others

use moderate laser power but still high enough

to produce excited states of the investigated spe‐

cies, such as Laser Induced Fluorescence [12] or

Raman Spectroscopy [13]; (c) and on the low end

of applied laser power, holographic interferometry

[14] and laser scanning. Laser scanning is nowa‐

days frequently used, typically for producing three

dimensional models of historical sites [15] and

caves [16], or to produce real time topographic

data for documentation of excavations.

The task of such instrument is to assign to each

point reflecting a laser beam within its range of

operation X, Y, Z coordinates, producing a so called

point cloud, which is the raw data for subsequent

modelling. This task can be achieved in two man‐

ners. On one hand a pulsed laser can be employed,

measuring the round‐trip time of the pulse (time‐

of‐flight, TOF), which is the most widely used tech‐

nique for long distance measurements (meters to

kilometres). On the other hand, continuous‐wave

lasers can emit at varying modulation lengths and

detect the phase‐shift of the reflected signal, from

which the distance to the reflecting object can be

calculated. When compared to the TOF technique,

the phase shift technology considerably speeds

up the registration. In our particular case, 120,000

points/second can be achieved with high accuracy,

compared to about 4,000 points/second by TOF,

although this technique is not appropriate for

very long distance measurements such as air‐

borne scanning. Modulated light also allows the

scanner to ignore light from sources other than a

laser, hence interference is substantially reduced.

The scanner works by sending a light beam into

the centre of a rotating mirror. As shown in fig‐

ure 2, the mirror deflects the laser on a vertical

rotation around the environment being scanned.

After interacting with the object, the beam is re‐

flected back into the mirror and the phase shift

of the wave is measured. Using encoders to sim‐

ultaneously record both the mirror rotation and

34 e‐conservation

CHRISTIAN DIETZ, GIANLUCA CATANZARITI & ALFREDO JIMENO MARTÍNEZ

the horizontal rotation of the scanner, X, Y and Z

coordinates of each point can be calculated.

However, phase shift technology is more suscep‐

tible to effects caused by phenomena other than

total reflection of the incoming beam on the sur‐

face to measure. This undesired effect is studied

in the present work in order to obtain infrared

data of painted artworks making use of a three

dimensional laser scanner emitting at 785 nm and

equipped with phase shift detection. Colour infor‐

mation for each scanned data point was simultane‐

ously obtained, making use of a digital camera

coupled to the scan head of the instrument.

Artworks

Studies were carried out on three different paint‐

ings. The first, an oil painting on cardboard covered

with cotton, is a modern interpretation of Melozzo

da Forlì's "Music‐making Angel", by A. Criado Por‐

tal (2010). The second is an untitled work, painted

in acrylic on canvas, showing geometrical forms

with underlying drawing, made with charcoal.

This painting was made in 2009 as a reference

object for IRR studies at the Faculty of Fine Arts

of the Complutense University. The third dates to

the late 16th or beginning of the 17th century and

shows Saint Mark the Evangelist together with

his symbol, the lion. This painting, of unknown

authorship, belongs to the church of Bujarrabal

(Guadalajara, Spain) and is currently being re‐

stored at the Faculty of Fine Arts of the Complu‐

tense University. It is painted on a wooden panel

and attributed to the Castilian School. Figure 3

shows photographs of these paintings.

Instrumental

The 3D laser scanner used was a Faro Photon 80

with software Faros Scene V4.6 for scan control

and data evaluation. Colour option was provided

via a Nikon D300 digital camera with AF Fisheye

35e‐conservation

INFRARED REFLECTOGRAPHY USING 3D LASER SCANNING

Figure 2. Instrumental configuration for a laser scanner withphase shift (∆φ) detection. Legend: 1 ‐ laser diode; 2 ‐ rotatingmirror; 3 ‐ target; 4 ‐ photodiode; 5 ‐ reference oscillator andphasemeter.

Figure 3. Studied artworks and their respective dimensions. From left to right: Music making Angel, 28x33 cm; Untitled, 38x46cm; and Saint Mark the Evangelist, 65.5x89.5 cm.

lenses (Nikkor de 10.5mm 1:2.8G ED), mounted

in horizontal position above the scanning unit.

In order to pinpoint the exact position of the art‐

work under investigation with respect to the instru‐

ment, first a 360º low resolution scan was carried

out. Scans were then taken for selected areas in

full resolution (0,009° vertical, 0,00076° hori‐

zontal) at a recording speed of 120.000 points/

second. Finally, the camera was moved to the

mirror position of the scanner and referenced

optical images were taken.

The instrumental setup used for IRR consisted in

a Hamamatsu InGaAs camera (Mod. C10633‐23),

providing high sensitivity in the wavelength range

from 900 to 1700 nm. The camera was connected

to a real‐time monitor via the standard video out‐

put. Connection to a PC went through a standalone

video image processor (C2741‐62), allowing shad‐

ing correction, contrast enhancement, averaging,

Y‐correction and edge extraction. For image capture,

the paintings were illuminated using two 100 W

halogen lamps.

Results and Discussion

The performance of the instrument matched the

expectations, taking into account the rather li‐

mited part of the IR spectrum under observation.

In general, it can be observed that clear colours

tend to gain transparency and the grey scale be‐

comes uniform, revealing several details which

have been corrected by the painter in the last stage

of the work. In the picture of the angel, a white

pearl, initially forming part of the ornamental

headband worn by the angel, but finally over‐

painted, can be clearly distinguished, as shown in

figure 4. In the centre of the same figure, in the area

just above the marked arrow, tracing details of the

angel’s hairstyle which have also been slightly

changed in the final version can be appreciated.

The same applies to the eyebrow and horizontal

diameter of the angel’s eye, which appear to have

different angles and size, respectively, when com‐

pared to the finished work.

However, charcoal sketches drawn directly onto

the support lack sufficient resolution and have

to be more deduced than detected, as shown in

figure 5, in the example of the untitled picture.

In this case, the underdrawing shows a sitting

man with head and beard, which can be clearly

distinguished in the reflectography image. In con‐

trast to that, the inner light and dark orange col‐

oured geometrical figures of the original have not

become completely transparent in the scanned

image, in particular the darker one, superimpos‐

ing the underlying drawings. This is not surprising

as penetration depth of infrared radiation increases

with growing wavelength. Obrutsky et al. presented

a very illustrative example for this fact [17], where

a picture showing a horse head was subsequently

investigated in the visible, IR‐A, IR‐B and IR‐C

region. The longer the wavelength, the clearer two

horses in the background could be distinguished,

which formed part of the original painting but were

finally overpainted by the artist. Nonetheless,

the first traces of the charcoal drawings, such as

the lower border of the left arm and other features

delimiting the figure, already appear using near

infrared light, as shown at some details highlighted

in figure 5A.

Hence, it is desirable to dispose of alternative

laser wavelengths, for example at 1400 nm and

36 e‐conservation

Figure 4. Comparison of IR (left) and VIS (right) images. Thearrow indicates a pearl which is not part of the final design.

CHRISTIAN DIETZ, GIANLUCA CATANZARITI & ALFREDO JIMENO MARTÍNEZ

2200 nm, for which suitable laser diodes are avail‐

able. Necessary changes within the laser head

would be relatively easy to achieve, for instance

by a movable mirror focusing light emitted by the

additional diodes into the optical path of the ori‐

ginal. From the detector side the issue is a bit more

complicated, as the phasemeter has to be set to

the changing wavelength, which possibly may be

done by hardware changes and/or corresponding

software correction algorithms.

Taking into account the instrument’s current re‐

striction to a specific wavelength in the real near

infrared region (785 nm), the gained information

is still highly valuable, although not as complete

as an IRR image, which covers the whole infrared

region.

This may be highlighted with a comparison of scan

and IRR data obtained from the painting of Saint

Mark the Evangelist. The underlying sketches,

37e‐conservation

Figure 5 (above). Detail of scanned (A) and IR reflectography (B) image on the untitled painting. In the first image, the uppercircle contains a hat, the middle circle shows a right hand supporting the head, the lower circle has a left elbow, the oblique lineshows a right arm, and the rectangle contains some horizontal lines.

Figure 6 (below). Colour photography (A), scanned (B) and reflectography image (C) of the lion belonging to the painting ofSaint Mark the Evangelist.

A B

A B C

INFRARED REFLECTOGRAPHY USING 3D LASER SCANNING

probably done in oil paint rather than charcoal,

reflect almost entirely the final composition of

the painting, outlining the figures and landscape

which were later on filled with colour. Looking

into the reflectography data, this becomes par‐

ticularly evident in zones like the hand of the

saint holding the paint brush and the clothing

he wears (data not shown). As it can be seen in

figure 6, showing a detail of the lion, Saint Mark’s

symbol, situated in the lower left corner of the

panel, generally the more profound paint layers,

such as traces of the forehead of the animal, can

be distinguished more clearly making use of the

IRR image. In turn, details of the superficial paint

layers, such as the final touches to improve the

appearance of the eyes, can be more clearly ap‐

preciated in the near infrared zone, correspond‐

ing to the scanned image, as shown in figure 7.

The ultimate compositional features, such as li‐

on’s beard, can be confirmed by both methods,

as the last paint layers are the first to become

transparent using infrared light.

The only problem encountered during data record‐

ing is the total reflection of the IR beam, occur‐

ring to a certain amount when hitting the painting

close to the right angle, causing plain white zones

in the image. To overcome this, the artwork has

to be situated slightly above or below the optical

path of the scan head.

The laser scanner used splits the beam into 3 com‐

ponent parts, operating on 3 different modula‐

tion lengths, providing an accuracy of 0.58 mm

within the specific range of the measured target,

with a vertical and horizontal resolution of 0.009º

and 0.00076º, respectively. These can be considered

to be very good values for a middle range scanner,

nonetheless not enough to reveal very fine details

of a painting’s topography, such as brush strokes.

Furthermore, an additional imprecision is intro‐

duced just by the fact that the used IR radiation

penetrates into the investigated surface. Nonethe‐

less, a high resolution 3D model of components

such as the frame or, in case the artwork is in‐

vestigated in its original location (e.g. church,

cathedral, castle) the paintings’ adjacent sur‐

rounding, as well as topographic data in case of

cave paintings, can be easily obtained from the

point clouds recorded during scanning.

A final issue which may be discussed here is the

total amount of radiation to which the painting

has to be exposed during the analysis. It is well

known that incident light causes ageing processes

in pigments and binding media, reason for which

preservation of artworks, in particular old and

highly valuable pieces always require the limita‐

tion of light exposure to a minimum.

The measure of the total power of electromagnetic

radiation landing on a particular surface, including

infrared, ultraviolet, and visible light, is defined

as irradiance, a quantity for which the SI unit is

Watt per square meter. The exact calculation of

this value for a given light source is not an easy

task, but with some simplifications one may get

a good estimate of its dimension. Assuming that

the source is emitting at a particular wavelength,

that neither absorption nor refraction of light oc‐

curs in the medium and that the magnetic suscep‐

tibility is negligible, irradiance simply decreases

with the square of the distance from the source.

This is because the overall power is constant but

the illuminated area grows squared with distance.

38 e‐conservation

Figure 7. Detail of the lion’s right eye obtained by scannedimage (left) and IR reflectography (right).

CHRISTIAN DIETZ, GIANLUCA CATANZARITI & ALFREDO JIMENO MARTÍNEZ

In the case of a directional laser beam, the problem

is that the radiation does not distribute uniformly

in all directions. During scanning, most of the time

a given point at the surface does not receive any

energy at all, but a high energy over a short frac‐

tion of time, resulting in a low average irradiation

but with punctual higher values. The average ra‐

diant emittance value for an object situated at a

given distance from the scanner may hence be

calculated as:

I ⋲ P / 4 π d2

where P is the power of the light source and d the

distance. In our particular case the laser power is

22 mW and the distance to the artwork was set to

about two meters, obtaining an irradiance value

of 0.44 mW/m2. For calculation of short term ex‐

posure, we have to use the laser beam diameter,

which is, following the manufacturer specifications,

a circular spot of about 3 mm diameter at exit.

Here we calculate an irradiance of more than 3000

mW/m2, which is a bit more than the double of sun‐

light intensity. This peak value will be achieved for

the spot area over which the beam passes no longer

than the maximum pulse duration of the laser, which

is at full resolution 0.0076 seconds only and de‐

creases proportionally with the resolution.

Tungsten halogen incandescent lamps, as those

commonly employed for illumination in IRR, are

thermal radiators, which means that light is gener‐

ated by heating a solid filament to high tempera‐

tures. Assuming that the spectral power distribu‐

tion roughly follows that of a blackbody radiator,

up to 85 percent of the emitted energy lies in the

infrared region of the spectrum, another 15‐20

percent falls into the visible and about 1 percent

into the ultraviolet wavelengths. The total radi‐

ation follows a fourth power law with respect to

the tungsten wire temperature, which means that

increasing temperature shifts the spectral distri‐

39e‐conservation

bution into the visible region of the spectrum, the

area under the resulting bell shaped curve rep‐

resents the total irradiance.

Under ideal conditions and for the aforementioned

distance, for a 100 W halogen bulb we would achieve

an irradiance of 2000 mW/m2 for the total incident

electromagnetic radiation, spanning the wave‐

length region between 200 and 3000 nanometres.

Though heat dissipation in air would considerably

diminish the real irradiance in the example, in

practice these lamps have to be situated much

closer to the artwork when taking reflectography

images, while the scanner may be placed as far as

ten meters from the object without losing much

of resolution. Furthermore, one has to consider

that the spectrum emitted by incandescent lamps

has a considerable amount of light with wave‐

lengths shorter than infrared, which in general is

considered to cause more damage to the artwork.

This is particularly true for darkening of yellow pig‐

ments such as chrome yellow [18], where exposure

to UV‐light causes superficial reduction of the origi‐

nal Cr(VI) to Cr(III). Possibly the most important

factor when comparing both techniques is the total

exposure time to light, ranging from tenths of

minutes for taking mosaic pictures in IRR to the

duration of a laser pulse when making use of scan‐

ning technology.

Hence, peak values are in the same order of mag‐

nitude for this given example, but for total irra‐

diance, the values obtained for the scanner are

about three orders of magnitude lower.

Conclusions

A direct comparison of infrared reflectography

versus a 3D laser scanning device for investiga‐

tion of artworks revealed that both provide com‐

parable information in the near‐infrared region.

For the mid and far‐infrared regions, revealing

information of deeper paint layers such as the un‐

INFRARED REFLECTOGRAPHY USING 3D LASER SCANNING

e‐conservation40 e‐conservation

derdrawing, IRR appears to be the more suitable

method, since the laser diodes emission is limited

to a well defined wavelength in the NIR zone.

Nonetheless, the scanning technology provides

several advantages over classical IRR as coloured

and fully measurable 2 or 3D models can be achieved

within minutes, even though further modelling,

for instance surface topographic analysis and rep‐

resentation, requires additional manpower and

computing time. False colour IR pictures are also

available, using scan data post‐processing in

dedicated software. The technique is especially

suitable for paintings of great dimensions and

with difficult accessibility, as it can be operated

from a considerable distance to the object and

does not require mounting additional structures,

such as a scaffold.

Peak values of light irradiation may be considered

to be in the same order of magnitude for both

techniques, but much longer exposure times are

necessary in case of incandescent lamps, which

contrary to the laser, emit a considerable portion

of more energetic and hence more harmful light.

On the other hand, the overall irradiance for the

laser technique is orders of magnitude lower.

The technique has clearly shown potential to be

developed into a competitive instrument with re‐

spect to IRR. This could be relatively easy to achieve

by the incorporation of laser diodes emitting in

the mid and far‐infrared region into the laser head

and the corresponding soft‐ and hardware changes

on the detector side.

Acknowledgments

We would like to thank Consuelo Dalmau and Silvia

García Fernández‐Villa, from the Department of

Painting and Restoration of the Faculty of Fine

Arts, Complutense University, for facilitating the

access to most of the investigated artworks and

helping with the reflectography raw data. Antonio

Criado Portal is gratefully acknowledged for pro‐

viding original artwork and the corresponding doc‐

umentation of the creation process. Thanks to Val‐

entín Garcia Baonza for the fruitful discussions and

advice regarding infrared emitting laser systems.

References

[1] F. Casadio, and L. Toniolo, “The analysis of

polychrome works of art: 40 years of infrared

spectroscopic investigations”, Journal of Cultural

Heritage 2(1), 2001, pp. 71‐78, doi:10.1016/

S1296‐2074(01)01107‐4, URL

[2] D. Saunders, R. Billinge, J. Cupitt, N. Atkinson,

and H. Liang, “A New Camera for High‐Resolution

Infrared Imaging of Works of Art”, Studies in Con‐

servation 51, 2006, pp. 277‐290

[3] M. Attas, E. Cloutis, C. Collins, D. Goltz, C.

Majzels, J.R. Mansfield, and H.H. Mantsch, “Near‐

infrared spectroscopic imaging in art conservation:

investigation of drawing constituents”, Journal

of Cultural Heritage 4(2), 2003, pp. 127‐136,

doi:10.1016/S1296‐2074(03)00024‐4, URL

[4] F. Ospitali, A. Rattazzi, M.P. Colombini, A.

Andreotti, and G. di Lonardo, “XVI century wall

paintings in the “Messer Filippo” cell of the tower

of Spilamberto: Microanalyses and monitoring”,

Journal of Cultural Heritage 8(3), 2007, pp. 323‐

327, doi:10.1016/j.culher.2007.02.004, URL

(available at URL [pdf])

[5] G. Verhoeven, “Imaging the invisible using

modified digital still cameras for straightforward

and low‐cost archaeological near‐infrared pho‐

tography”, Journal of Archaeological Science

35(12), 2008, pp. 3087‐3100, doi:10.1016/

j.jas.2008.06.012, URL

CHRISTIAN DIETZ, GIANLUCA CATANZARITI & ALFREDO JIMENO MARTÍNEZ

[6] D. Ambrosini, C. Daffara, R. Di Biase, D. Paoletti,L. Pezzati, R. Bellucci, and F. Bettini, “Integratedreflectography and thermography for woodenpaintings diagnostics”, Journal of Cultural Heritage11(2), 2010, pp. 196‐204, doi:10.1016/j.culher.2009.05.001, URL

[7] A.C. Felici, G. Fronterotta, M. Piacentini, C. Ni‐colais, S. Sciuti, M. Vendittelli, and C. Vazio, “Thewall paintings in the former Refectory of the Trinitàdei Monti convent in Rome: relating observationsfrom restoration and archaeometric analyses toAndrea Pozzo’s own treatise on the art of muralpainting”, Journal of Cultural Heritage 5(1), 2004,pp. 17‐25, doi:10.1016/j.culher.2003. 07.001, URL

[8] M. T. Doménech‐Carbó, “Novel analytical meth‐ods for characterising binding media and protec‐tive coatings in artworks”, Analytica Chimica Acta621(2), 2008, pp. 109‐139, doi:10.1016/j.aca.2008.05.056, URL

[9] B. Giussani, D. Monticelli, and L. Rampazzi,“Role of laser ablation–inductively coupled plasma‐mass spectrometry in cultural heritage research:A review”, Analytica Chimica Acta 635(1), 2009,pp. 6‐21, doi:10.1016/j.aca.2008.12.040, URL

[10] A.V. Rode, K.G.H. Baldwin, A. Wain, N.R. Mad‐sen, D. Freeman, Ph. Delaporte, and B. Luther‐Davies, “Ultrafast laser ablation for restorationof heritage objects”, Applied Surface Science254(10), 2008, pp. 3137‐3146, doi:10.1016/j.apsusc.2007.10.106, URL

[11] M. Brai, G. Gennaro, T. Schillaci, and L. Tran‐chita, “Double pulse laser induced breakdownspectroscopy applied to natural and artificialmaterials from cultural heritages: A comparisonwith micro‐X‐ray fluorescence analysis”, Spectro‐chimica Acta B 64(10), 2009, pp. 1119‐1127,doi:10.1016/j.sab.2009.07.027, URL

[12] V. Raimondi, G. Cecchi, D. Lognoli, L. Palombi,

R. Grönlund, A. Johansson, S. Svanberg, K. Barup,and J. Hällström, “The fluorescence lidar tech‐nique for the remote sensing of photoautotrophicbiodeteriogens in the outdoor cultural heritage:A decade of in situ experiments”, InternationalBiodeterioration & Biodegradation 63(7), 2009,pp. 823‐835, doi:10.1016/j.ibiod.2009.03.006,URL

[13] D. Creagh, A. Lee, V. Otieno‐Alego, and M.Kubik, “Recent and future developments in theuse of radiation for the study of objects of culturalheritage significance”, Radiation Physics andChemistry 78(6), 2009, pp. 367‐374, doi:10.1016/j.radphyschem.2009.03.005, URL

[14] V. Tornari, "Laser interference‐based tech‐niques and applications in structural inspectionof works of art", Analytical and Bioanalytical Chem‐istry 387(3), 2007, pp. 761–780, doi: 10.1007/s00216‐006‐0974‐4, URL

[15] P. Martín Lerones, J. Llamas Fernández, Á.Melero Gil, J. Gómez‐García‐Bermejo, and E. Za‐lama Casanova, ”A practical approach to makingaccurate 3D layouts of interesting cultural herit‐age sites through digital models”, Journal of Cul‐tural Heritage 11(1), 2010, pp. 1‐9, doi:10.1016/j.culher.2009.02.007, URL

[16] J. Luis Lerma, S. Navarro, M. Cabrelles, andV. Villaverde, “Terrestrial laser scanning and closerange photogrammetry for 3D archaeologicaldocumentation: the Upper Palaeolithic Cave ofParpalló as a case study”, Journal of Archaeolo‐gical Science 37(3), 2010, pp. 499‐507, doi:10.1016/ j.jas.2009.10.011, URL

[17] A.E. Obrutsky and D. Acosta, “Infrared reflec‐tography, an NDT technique for images diagnosis”,presented at the 3rd Pan American Conference forNondestructive Testing ‐ PANNDT, Rio de Janeiro,Brazil, June 2‐6, 2003 (available in Spanish atURL [pdf])

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41e‐conservation

[18] L. Monico, G. Van der Snickt, K. Janssens, W.

De Nolf, C. Miliani, J. Dik, M. Radepont, E. Hendriks,

M. Geldof, M. Cottez, "Degradation Process of Lead

Chromate in Paintings by Vincent van Gogh Studied

by Means of Synchrotron X‐ray Spectromicroscopy

and Related Methods. 2. Original Paint Layer Sam‐

ples", Analytical Chemistry 83, 2011, pp. 1224–

1231, doi:10.1021/ac1025122, URL

CHRISTIAN DIETZContact: [email protected]

Christian Dietz received his MSc from Technische

Hochschule Darmstadt in 1995. Then he moved

to Complutense University of Madrid, where he

obtained his PhD in Chemistry in 2001. The fol‐

lowing 7 years of investigation, at the Department

of Analytical Chemistry, were mainly devoted to

instrumental and method development in metal

speciation analysis, with a special focus on sample

treatment, but as well bio‐environmental studies

in general and waste water management in par‐

ticular. In 2008 he was involved in the establish‐

ment of the Centre for Archaeometry and Archae‐

ological Analysis at the Complutense University

of Madrid, where he currently works dedicated to

instrumental analysis and dating of a wide range

of archaeological artefacts. He also covers non

invasive survey techniques in archaeology such

as geophysical prospections and laser scanning.

GIANLUCA CATANZARITIContact: [email protected]

Gianluca Catanzariti received his MsC in Geolo‐

gical Science from the Universitá degli Studi di

Torino (Italy) in 1999. Currently he is working on

his PhD thesis centred on archaeomagnetic meas‐

urements at the Faculty of Physics, Dpt. of Earth

Sciences at the Complutense University of Madrid.

At the same time he is employed as technician at the

universities Centre for Archaeometry and Archae‐

ological Analysis, where is is mainly devoted to

geophysical prospection methods such as ground

penetrating radar, a field where he also holds years

of experience at an Italy based private company.

Further, he is a specialist in archaeomagnetic

dating techniques and was actively involved in

the establishment of the paleosecular calibration

curve for the Spanish Peninsula.

ALFREDO JIMENO MARTÍNEZContact: [email protected]

Alfredo Jimeno received his higher education in

History and Archaeology at the University of Zar‐

agoza, where he obtained his PhD in 1981. His

teaching and research activities started in 1976

at the College of Soria (University of Zaragoza),

moving to the Complutense University of Madrid

in 1986. He was appointed Director of the Centre

for Archaeometry and Archaeological Analysis at

the same university in 2007. His extensive research

activities, embodied in a dozen books and over 150

articles, focus on the early history of the Spanish

Central Plateau, covering the Bronze Age, Iron Age

and the Romanization. His work at international

level is reflected in the joint management of dif‐

ferent projects on "The origin of food production

in the Blue Nile area”, as a member of the Archae‐

ological Mission of the Complutense University in

Sudan (1988‐1999) and he is correspondent of the

German Archaeological Institute. Currently, he is

a member of the Scientific Committee of “Duques

de Soria” foundation and of the Editorial Board of

the U.C.M. “Complutum” magazine. In 2005 he was

appointed Commissioner for the International

Exhibition "Celtiberians”, organised by the Junta

de Castilla y León, entity which also named him

director of the site management plan for Numancia

(1994‐present).

CHRISTIAN DIETZ, GIANLUCA CATANZARITI & ALFREDO JIMENO MARTÍNEZ

42 e‐conservation

A REFLECTION ON THE PREVENTIVECONSERVATION OF ARCHAEOLOGICAL WOOD

AND THE EFFECTS OF MASS TOURISM

The Case Study of the Vasa Warship

By Cristina Cabello‐Briones

Introduction

Tourism is and must be acceptable for any museum.

However, large‐scale tourism has a direct nega‐

tive effect on collections such as that of the Vasa

Museum. Although it is clear that environmental

conditions affect archaeological wood, preventive

conservation of such collections has not been ex‐

tensively considered. Wooden shipwrecks have

been studied from several perspectives mainly in

research that refers to material degradation and

new treatments. The main objective of this article

is to raise public awareness of this topic and high‐

light the benefits of a well planned preventive

conservation strategy in order to safeguard ar‐

chaeological wooden cultural artefacts. Before

analysing the example of the Vasa Museum, a

brief description of the effects of environment

and tourism on archaeological wood and an in‐

troduction to preventive conservation manage‐

ment are presented.

Preventive Conservation of Archaeological Wood

Wood equilibrates with its environment. If the sur‐

rounding conditions change, wood reacts to the

abundance or absence of moisture in the air and

will expand or contract. Thomson [1] recommen‐

ded 19‐24 °C and 45‐55% RH as ideal conditions

for the museum environment housing unpainted

wooden objects. At lower RH values, wood cracks,

becomes brittle and shrinks. Above 65% RH, mold

growth is promoted and swelling increases. Main‐

taining the relative humidity between 50‐60%

reduces most of the visible damage. However, Mi‐

chalski [2] reminds us that "the specifications for

temperature and humidity in related literature rep‐

resent the lowest common denominator amongst

the needs of objects, and not necessarily the op‐

timum for each". Each case needs to be analysed

individually and on many occasions this means

testing the decisions in practice.

When an object is mechanically stable, most dam‐

age is due to RH fluctuations. These can eventu‐

ally lead to cracking, checking and warping of the

wooden artefact. In addition, fast changes in rel‐

ative humidity cause internal stresses due to dif‐

ferences of moisture between inner and outer

areas [3, p. 34]. Therefore, an ideal environment

is achieved when no cyclic variations occur. Slight

shifts are permitted if the change is slow, varying

at maximum over ±5% range [4, p. 269].

Relating to temperature, every 10 °C increase

doubles the average rate of organic reactions [3,

p. 40]. Therefore, lower temperature levels (15‐

20 °C) slow these rates and offer a comfortable

environment to visitors.

Light affects wood in several ways. The most severe

damages are connected with chemical bond break‐

age, free radical formation and the subsequent

depolymerisation of polymers. In addition, wood

44 e‐conservation

Archaeological wood is an organic material, sensitive to environmental conditions. Wood, even when

treated with polyethylene glycols, adapts to the surrounding environment with physical and chemical

reactions that may be detrimental to its preservation. In addition, excessive tourism has a negative

effect on the museum environment once its indoor conditions fluctuate directly with the number of visitors.

In order to minimize the effects of a negative climate caused by mass tourism on archaeological wood

collections, preventive conservation measures should be taken. To illustrate an effective preventive

conservation management, the case of the Vasa museum in Stockholm, which houses the 386 years old

Vasa warship, is discussed.

CRISTINA CABELLO‐BRIONES

that has been exposed to the visible and ultra‐

violet wavelengths radiation of daylight under‐

goes colour change [5]. Experts agree on a range

between 300 and 50 lux as appropriate for safe

display, although lighting between 200 and 50 lux

should be used for severely deteriorated objects

considering that 50 lux is the minimum level re‐

quired for colour perception and adequate visi‐

bility [4, p. 268].

Treatment with polyethylene glycol (PEG) has be‐

come the most common application for the pre‐

servation of many kinds of waterlogged wooden

remains. The technique involves the impregnation

of wood with PEG solutions so that the water in the

cell walls is replaced by the preservative. The pro‐

cess is focused on the stabilisation of the timbers’

dimensions and bulking of the wood structure.

Highly degraded wood treated with PEG changes

its dimension regularly according to the relative

humidity though its range of change is smaller

than that of sound wood [6]. For wood treated

with any molecular weight of PEG, unless it is con‐

tinually recoated, exposure to high RH (higher

than 60%) will make the surface sticky and could

leach out the impregnant [7]. In addition, PEG is

hygroscopic and transports ions and dissolved

oxygen within the treated wood when there are

humidity fluctuations causing both physical and

chemical problems [8].

Impact of Large‐scale Tourism on the CulturalHeritage

Tourism affects tangible heritage in several and

diverse ways: visitors release heat, water vapour

and carbon dioxide; they transport external par‐

ticles and the accumulation of dust can lead to

further cleaning that may damage surfaces; they

also generate turbulence, which increases the

deposition rate of particulate matter [9, pp. 127‐

140]. In addition, a large number of people visit

museums on rainy days and their wet coats intro‐

duce additional moisture.

Although it is difficult to differentiate between in‐

door environmental variations caused by visitors and

the effects of outdoor climate, it is clear that the

way tourism in museums is organised nowadays

has a direct connexion with environmental fluctu‐

ations. An adult releases approximately 60 grams

of water vapour per hour and 60 watts per square

metre of body surface as heat [10, p. 20], affecting

ambient relative humidity. Negative environmental

condition cycles are related to successive waves

of tourists who access the museum. For example,

measurements in the Kunsthistorisches Museum

in Vienna during and after the Bruegel exhibition

in 1998 showed an increase in heat and moisture

directly caused by the tourism flows [9, p. 132].

To avoid the collection itself and/or the building

acting as buffer elements, environmental control

systems must cope with these sudden stresses,

maintaining a constant climate during and after

the visiting hours.

Preventive Conservation Management

Although large‐scale visitor access involves risk

for cultural objects, the public is necessary to

keep a museum open. A large number of visitors

increases the prestige of a museum and ensures

funding as demonstrated by the Delphi survey of

owners and managers of historic properties across

the United Kingdom [11]. The survey shows that

the highest ranked criterion for priority in fund‐

ing is related to the ‘significance’ of the heritage.

This is measured through its uniqueness and rel‐

evance for the community as well as its public

appeal. However, pressures imposed by visitors

are not considered to be a major criterion for de‐

termining conservation funding.

45e‐conservation

PREVENTIVE CONSERVATION OF ARCHAEOLOGICAL WOOD

Mass tourism is an economic resource and in the

context of indoor climate, the key is to achieve the

right balance between the increasing demand for

access and the need to protect the cultural herit‐

age itself.

Different measures can be carried out to reduce

the impact of tourism. Not including the cultural

object/site in promotional material could reduce

the awareness of the attraction [12]. Another

solution could be to display the most valuable

objects of a collection in showcases or substitute

them with replicas. However, display cases are

not always the best conservation solution [13]

and ethical issues as authenticity, provenance

and context could arise [14]. According to Young

and Cassar [15], the type of measure depends on

the uniqueness and vulnerability of the cultural

artefact, its local or international importance,

the ability to make facsimiles, the rate of degrada‐

tion from environmental conditions and the quality

of the protective environment.

In these days of rising cost and lack of funding,

preventive conservation management is the best

option. According to Cassar’s definition, preventive

conservation management is “the creation and

maintenance of an environment that limits the

decay of museum objects to the absolute minimum

consistent with public access” [10, p. 3]. A pre‐

servation plan allows the analysis of deteriorating

environmental conditions caused by the influx of

tourist and developing a strategy to protect the

cultural artefacts. Additionally, environmental

monitoring is a reliable source of information that

can be used to assess risks and understand dam‐

ages and impacts.

Case Study: Preventive Conservation of theVasa Warship

The Swedish King Gustavus Adolphus ordered the

Vasa (figure 1) to be built in 1625 due to the Thirty

Years' War. Although a number of different tree

species were used in the Vasa, 90% of the weight

46 e‐conservation

CRISTINA CABELLO‐BRIONES

Figure 1. The Vasa warship. Photo by Anneli Karlsson, the Swedish National Maritime Museums, © All rights reserved.

47e‐conservation

Figure 2. Stern view of the Vasa warship. Photo by Karolina Kristensson, the Swedish National Maritime Museums,© All rights reserved.

PREVENTIVE CONSERVATION OF ARCHAEOLOGICAL WOOD

of the hull is oak. The ship sank, fully equipped, on

its maiden voyage out of Stockholm harbour in

1628, and was raised to the surface in 1961. On

the salvage, the timbers were found to be in re‐

markably good state (figure 2). The main reasons

were the absence of marine borers, fungi and rot

due to the near oxygen‐free conditions in the wa‐

ter and high concentration of hydrogen sulphide.

However, the surface of the timbers was attacked

by cellulose‐degrading and sulphur‐meta‐bolizing

microorganisms. After salvage, exposure to atmo‐

spheric oxygen initiated a multitude of chemical

reactions threatening the long‐term preserva‐

tion of the ship such as oxidation of sulphur to

sulphuric acid, red‐ox reactions of sulphur and

iron compounds from bolts and cargo made of

iron, free radical reactions, acid hydrolysis and

oxidative degradation reactions of cellulose. The

conservation with PEG 1500 and 600 between 1962

and 1979 was followed by an air drying process for

another ten years1.

According to Emma Hocker [16, p. 4], conservator

at the Vasa Museum, the control of the indoor

environment has been a challenge, especially

due to the increasing public. The museum was

designed as a display case for the ship (figure 3)

with an internal airspace of about 105000 m3. The

original predictions of 600 000 visitors per year

have steadily increased until numbers reached 1.2

million visitors in 2008. The main reasons are its

value as source of information of a specific con‐

text and timeframe, but also the museum market‐

48 e‐conservation

Figure 3. General view of the Vasa Museum. Photo by Åke E:son Lindman, © All rights reserved.

CRISTINA CABELLO‐BRIONES

1 More detailed information can be found on the website ofthe Vasa Museum website at: http:// www.vasamuseet.se/en/Preservation‐‐Research/

by dehumidifying in advance when potential risks

are detected [16, p. 7]. Also a new energy‐effect‐

ive halogen‐based lighting system was installed

producing 30% less radiant heat [21].

Since installation, the hall climate has stabilised

considerably despite the greater number of visit‐

ors and the outdoor climate (figures 5 and 6). Out‐

breaks are not worsening either in coverage or

pH value and the almost 10% RH gradient over

the height of the ship was halved immediately

[16, p. 7].

ing strategy and the rise in the number of cruises

with Stockholm as a destination.

The museum former climate specifications were

set at 60% RH and 20 °C for summer months, and

57.5% RH and 17 °C in winter to avoid condensa‐

tion in the museum walls [17], equivalent to wood‐

moisture content of 10‐12%. Although this system

was sufficient for the winter months [18, p. 171]

when there were relatively few visitors, during

warm and wet summers, the RH rose to over 65%.

Temperature and RH gradients caused by the build‐

ing height [16, p. 5] were accepted as inevitable

but at lower levels [19] the RH at times reached

70% impacting the movement of the wood. The

climate system was under‐dimensioned.

After a record number of visitors during the rainy

summer of 2000, salt outbreaks were drawn to the

surface. Hydrated PEG could have dissolved salts

[20] from the material at high RH and these salts

could have precipitated on the wood surface when

the PEG was dehydrated at low RH. In addition,

large fluctuations were recorded near the entrance

to the museum shop and restaurant, where un‐

conditioned air could enter without control, and

in the viewing galleries at the stern, where stronger

lighting and visitors were concentrated [16, pp. 5‐

6]. It was then decided to reduce the RH from 60%

to 55% ± 4% and the year‐round temperature to

18.5 ± 1.5°C, equivalent to 10% moisture content

in the wood [16, p. 6].

In 2004, a new climate system with increased ca‐

pacity and sensitivity was installed in the ship hall

(figure 4). The principle is based on conditioned

air pumped in at low levels, rising around the ship

and sucked out through a duct near the ceiling

[18, p. 173] providing a protective curtain around

the ship. In addition, the visitor counter at the

museum entrance was incorporated into the steer‐

ing parameters. This measure allows preparation

49e‐conservation

Figure 4. Current climate‐control system above the ship stern.Photo by Karolina Kristensson, © All rights reserved.

Figure 5. Thermo‐hygrograph chart of the Vasa generated fromthe climate‐control system data at the Vasa Museum betweenthe 16th of June and the 21st of September 2003. The environ‐mental fluctuations were remarkable. Source: the Swedish Na‐tional Maritime Museums, © All rights reserved.

PREVENTIVE CONSERVATION OF ARCHAEOLOGICAL WOOD

However, this system could operate at maximum

capacity if the museum gives in to the pressure

of the long queues of visitors in peak season and

allows more public at one time. Then, a stable cli‐

mate could not be guaranteed [16, pp. 8‐9].

Conclusions

Ships that have been rescued from the sea are

among the most popular attractions worldwide,

making maritime museums highly profitable.

The great popularity of these museums ensures

continued funding for research, conservation,

acquisition and promotes cultural tourism. How‐

ever, it also increases the pressure to allow greater

numbers of visitors, making it difficult to maintain

a suitable preventive conservation programme.

Large‐scale tourism has a direct negative effect

on museum indoor climate environments. It pri‐

marily affects relative humidity causing rapid

fluctuations in short periods of time. Variations

in moisture enable the migration of water, dis‐

solved oxygen and salts into the PEG and wood,

and will initiate different chemical reactions.

The general concern nowadays is that the control

of relative humidity and temperature is the most

feasible preventive conservation measure in mu‐

seums with archaeological collections and high

tourism. Stabilizing the environment, avoiding

damaging extremes and fluctuations and main‐

taining the relative humidity low (around 55%)

will help preserve PEG treated marine wooden

artefacts [22].

Every museum should develop an environmental

management programme, a carefully elaborated

long‐term maintenance plan. This could include

technical aspects, such as dealing with monitor‐

ing and controlling of the museum environment,

and organisational issues, such as a visitor man‐

agement plan.

Acknowledgments

I wish to acknowledge the Vasa Museum. Special

thanks to Emma Hocker for generously giving me

part of her time to share her experience and know‐

ledge.

50 e‐conservation

Figure 6. Thermo‐hygrograph chart of the Vasa generated from the climate‐control system data at the Vasa Museum from the 16th

of June to the 21st of September 2009. RH and temperature fluctuations were minimized. Source: the Swedish National MaritimeMuseums, © All rights reserved.

CRISTINA CABELLO‐BRIONES

51e‐conservation

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Group Conference, 15‐18th September, 1981, Cana‐

dian Conservation Institute, Ottawa, ICOM Com‐

mittee for Conservation, Waterlogged Wood Work‐

ing Group, 1982, p. 250

[8] M. Sandström, Y. Fors, and I. Persson, "The Vasa's

New Battle. Sulphur, Acid and Iron", Vasa Studies 19,

The Vasa Museum, Stockholm, 2003, p. 21

[9] D. Camuffo, R. Van Grieken, H.‐J. Busse, G.

Sturaro, A. Valentino, A. Bernardi, N. Blades, D.

Shooter, K. Gysels, F. Deutsch, M. Wieser, O. Kim

and U. Ulrych, “Environmental monitoring in four

European museums”, Atmospheric Environment 35,

Supplement No. 1, 2001, doi:10.1016/S1352‐2310

(01)00088‐7 URL , also available at URL [pdf]

[10] M. Cassar, Environmental Management: guide‐

lines for museums and galleries, Museums & Galleries

Commission with Routledge, London, 1995

[11] B. Garrod and A. Fyall, “Managing Heritage

Tourism”, Annals of Tourism Research 27(3), 2000,

pp. 682‐708, doi: 10.1016/S0160‐7383(99)00094‐8,

URL

[12] M. Drdácky, T. Drdácky, D. Creighton, “Impact

of Cultural Tourism upon the Diversity of Built Her‐

itage”, position paper of the PICTURE project Pro‐

active management of the Impact of Cultural Tourism

upon Urban Resources and Economies, 2007, avail‐

able at URL [pdf] (accessed November 2010)

[13] D. Camuffo, G. Sturaro, and A. Valentino,

“Showcases: a really effective mean for protecting

artworks?”, Thermochimica Acta 365(1‐2), 2000,

pp. 65‐77, doi:10.1016/S0040‐6031(00)00614‐6,

URL

[14] M. Cassar, P. Brimblecombe, T. Nixon, C. Price,

C. Sabbioni, C. Saiz Jimenez, and K. Van Balen,

Technological requirements for solutions in the con‐

PREVENTIVE CONSERVATION OF ARCHAEOLOGICAL WOOD

servation and protection of historic monuments and

archaeological remains, European Parliament, Kirch‐

berg, Luxembourg, 2001, p. 43, available at URL

[pdf] (accessed July 2010)

[15] A. Young and M. Cassar, “Indoor Climate and

Tourism Effects ‐ a UK perspective”, in M. Drdácký

(ed.), European Research on Cultural Heritage, State‐

of‐the‐Art Studies, Vol. 2, ITAM 2004, Academy of

Sciences of the Czech Republic, Prague, 2004, pp.

405‐412, available at URL [pdf] (accessed August

2010)

[16] E. Hocker, “Maintaining a Stable Environment:

Vasa´s New Climate‐ Control System”, Journal of

Preservation Technology 41(2‐3), 2010, available at

URL [pdf] (accessed August 2010)

[17] B. Håfords, The climate of the Vasa Museum –

problems in coordinating the museum object and

the museum climate, 1997, available at URL (ac‐

cessed July 2010)

[18] I. Hall Roth and L. Malmberg, “Save the Vasa‐

An Introduction”, in P. Hoffmann, J. A. Spriggs, K.

Strætkvern and D. Gregory (eds.) Proceedings of

the 9th ICOM Group on Wet Archaeological Materials

Conference, Bremerhaven, 2005, ICOM, 2005

[19] E. Hocker, L. Dal, and F. Hocker, “Understand‐

ing Vasa’s Salt Problem: Documenting the Distribu‐

tion of Salt Precipitations on the Swedish Warship

Vasa”, in Proceedings of the 10th ICOM Group on Wet

Organic Archaeological Materials Conference, Bremer‐

haven, 2008: ICOM/RACM, Amersfoort, 2009, p. 479

[20] M.N. Mortensen, H. Egsgaard, S. Hvilsted, Y.

Shashoua and J. Glastrup, “Characterisation of the

polyethylene glycol impregnation of the Swedish

warship Vasa and one of the Danish Skuldelev Viking

ships”, Journal of Archaeological Science 34(8),

2007, p. 1217, doi:10.1016/j.jas.2006.10.012, URL

CRISTINA CABELLO‐BRIONESConservator

Cristina Cabello‐Briones is a recent postgraduate

in Preventive Conservation at Northumbria Uni‐

versity (Newcastle, UK). Her dissertation, assessed

with distinction, was about Preventive Conserva‐

tion of Wooden Wreck‐Hulls Retrieved from Un‐

derwater Maritime Environments. She is a first

class graduate in the Conservation and Restora‐

tion of Cultural Heritage from the Escuela Superi‐

or de Conservación y Restauración de Bienes Cul‐

turales de Madrid (Spain), speciality in paintings,

where she studied between 2002 and 2005. In

2008, she completed her second first class BA

degree in the History of Art at the Universidad

Autónoma de Madrid (Spain). Her dissertation

was about Historic Restorations of the Roma‐

nesque Mural Paintings at the National Museum

in Catalonia.

She has recently been awarded with La Caixa Schol‐

arship to study a PhD in Conservation in the United

Kingdom commencing in 2011.

Her most recent projects include the research of

the improvements to the Tate Gallery’s transit

frame wrapping system in order to save on ma‐

terials, time and handling of long term collec‐

tion care and the internship at the Reina Sofía

Museum (Madrid, Spain) assessing the risks for

cultural artefacts during mounting of exhibitions.

CRISTINA CABELLO‐BRIONES

52 e‐conservation

[21] Personal communication with Emma Hocker,

July 2010

[22] Y. Fors, Sulfur‐Related Conservation Concerns

for Marine Archaeological Wood. The Origin, Spe‐

cification and Distribution of Accumulated sulfur

with some Remedies for the Vasa, Doctoral Thesis,

Department of Physical, Inorganic and Structural

Chemistry, Stockholm University, 2008, p. 94

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THE USE OF GROUND PENETRATING RADARFOR THE ASSESSMENT

OF THE CONSERVATION STATEOF AN HISTORIC BUILDING

THE USE OF GROUND PENETRATING RADARFOR THE ASSESSMENT

OF THE CONSERVATION STATEOF AN HISTORIC BUILDING

By Lucian Cristian Ratoiu

This article proposes the elaboration of a dedicated database for monitoring the evolution of buried

structures or anomalies of the underground layers based on data collection after periodic surveys. The

use of a radar technique in establishing an efficient assessment protocol of the conservation condition

of historical building foundations proves to be a useful and accessible task due to its major advantages.

This non‐destructive technique with fast and accurate acquisition time meets the characteristic require‐

ments for the analysis of historic monuments. The possibility to perform periodic analyses allows the

monitorization required for long‐term preservation of cultural heritage. A case study is presented with a

survey of the foundation of an historic building, dating from the beginning of the 20th century and located

in the “Dimitrie Gusti” National Village Museum from Bucharest, Romania.

Research aims

The research comprises two main objectives: to

establish a useful and efficient instrument for

periodic monitoring and evaluation of the con‐

servation state or rehabilitation interventions on

historic monuments; and to elaborate a dedicated

system for data management that can provide

important information for long time preserva‐

tion of cultural heritage.

Introduction

Ground Penetrating Radar (GPR) is a well‐known

technique applied to identify buried structures,

cavities or anomalies below the ground surface

with the advantage to estimate the depth at which

they can be found. The technique is based on the

emission‐reception of electromagnetic pulses and

on their propagation in the soil.

The different scanning results are strongly de‐

pendent on the type of material encountered

which is characterized by the dielectric constants.

The radargrams resolution depends on factors

such as the central antennas frequency, sampling

frequency, antennas separation, and speed of

acquisition, among others. The environmental

responses, characterized through the resolution

and depth of the wave propagation are dependent

on the electromagnetic properties of the under‐

ground medium, the soil water concentration, the

electric conductivity or the presence of metals.

A fast survey by nondestructive means allows to

establish an efficient plan for periodic control of

historic building foundations. The aim of this re‐

search is to gather a particular database designed

Figure 1 and 2. The GPR system in Ruşeţu household – 2008(upper) and 2009 (lower).

e‐conservation 55

ASSESSMENT OF THE CONSERVATION STATE OF AN HISTORIC BUILDING BY GPR

to compare the results and to detect changes in

an early stage.

Regular monitoring ensures a constant determi‐

nation of minor changes in the historic monuments

foundations. Preventive interventions ensure a

long term preservation, thus avoiding major de‐

gradations such as cracks or internal displacements

of the walls structure.

Case Study

The Ruşeţu house, dating from the early 20th cen‐

tury, is a typical Romanian house that was trans‐

ported and reconstructed in the “Dimitrie Gusti”

National Village Museum, an open‐air ethno‐

graphic museum in Bucharest that houses tradi‐

tional Romanian architecture. The household con‐

sists of the dwelling house and some annexes to

shelter animals.

The house was built from common clay mixed with

vegetal aggregates, and the walls were painted

with lime. The facade and one side of the house

are provided with a low porch, supported on un‐

decorated wood poles, with a traditional roof

made by several layers of small pieces of wood.

On the back of the house, the roof also covers

the annexes.

The conservation problems were mainly caused

by capillarity moisture, especially on the annex

rooms, combined with the frailty of the specific

constituent materials.

Data Acquisition

The first acquisition campaign was made in 2008,

before the rehabilitation of the building. The ob‐

jective was to study the conservation state and to

record the possible anomalies of the underground.

Figure 3. Ruşeţu house in 2008, before rehabilitation.

56 e‐conservation

LUCIAN CRISTIAN RATOIU

In 2009, a second acquisition campaign was per‐

formed after the rehabilitation works, with the

objective of highlighting the differences before

and after the interventions.

For the data acquisition, two types of antennas

were used, with frequency at 500 MHz and 800

MHz. The use of two different antennas allowed

to investigate at higher depths with a higher res‐

olution at subsurface layers, and also to confirm

the recorded data. A very important factor is to

verify the environmental conditions, once the

high humidity of the soil caused by rain can influ‐

ence the measurements. Fundamental in obtain‐

ing accurate data is to adjust the system acqui‐

sition parameters to the analyze requirements.

Two parameters are essential. One is the samplingfrequency that has to be 10 times the center fre‐

quency of antenna in use. Second is the time win‐dow/number of samples which must be chosen

properly: to long window burdens the system un‐

necessarily and too short may ruin the data. Only

by keeping the same parameters used previously a

precise comparison of the results can be ensured.

An effective procedure for fast control on the re‐habilitation of historic monuments foundations

For the development of an efficient work guide used

in examination of cultural heritage, the strictness

Figure 4. Ruşeţu house in 2009, after rehabilitation.

Figure 5.The plan of the Ruşeţu houseand the scanning directions.

e‐conservation 57

ASSESSMENT OF THE CONSERVATION STATE OF AN HISTORIC BUILDING BY GPR

of interventions and investigations allowed by the

legislation should be considered as prior.

From this point of view, priority should be given

to non‐destructive and non‐invasive techniques

that provide high accuracy data that do not affect

the object.

Specific GPR information gathered requires an

organized and dedicated database that can allow

to compare and to follow the evolution of the con‐

servation state. In this case actions can be taken

at an early stage of decay, allowing to put in prac‐

tice preventive conservation measures.

Likewise, using the GPR technique with the aim of

evaluating the rehabilitation of building found‐

ations will prove to be an easy task, thanks to the

major advantages, characteristic for this fast and

non‐invasive method.

Using a comparative model for observing the ob‐

tained results will indicate modifications specific

for the time elapsed since the last data acquisition.

Figure 6 (below). Data acquisition from the 2008 campaign.

Figure 7. Data acquisition from the 2009 campaign.

58 e‐conservation

LUCIAN CRISTIAN RATOIU

The frequency of the acquisitions number will allow

a more accurate behavior of the ground founda‐

tions, which is mainly influenced by the compacta‐

tion movements of the soil layers caused by the

high percentage of capillary moisture or by the

new interventions carried out in that area.

The steps of the procedure must include: strict

delimitation of the area, description of the work

conditions, recording the data in the same envi‐

ronmental conditions, identical processing of the

data collected, resuming to new acquisitions after

a well established time, using the same settings

for the GPR system, and using at least two differ‐

ent frequency antennas to confirm the results

obtained.

Data Processing and Interpretation

Once collected, the data was processed using

routine corrections, provided by the dedicated

software – the post processing medium of GPR

data collected, to ensure a better visualization

of the results.

The radargrams allow to emphasize the layer anom‐

alies or eventual objects buried and to point out

their Cartesian coordinates. The runtime was kept to

ensure the same data post‐processing, the eventu‐

ally changing being the result of foundation evolu‐

tion, instead of data workflow differences.

On the radargrams recorded in the same years the

anomalies that correspond to the Cartesian co‐

ordinates are emphasized, which demonstrates

Figure 8. Procedure diagram.

Figure 9. Segment G‐H, 500 MHz antenna, 2008‐2009. Figure 10. Segment G‐H, 800 MHz antenna, 2008‐2009.

e‐conservation 59

ASSESSMENT OF THE CONSERVATION STATE OF AN HISTORIC BUILDING BY GPR

Figure 11. Segment A‐B, 500 MHz antenna, 2008.

Figure 12. Segment A‐B, 500 MHz antenna, 2009.

LUCIAN CRISTIAN RATOIU

60 e‐conservation

Figure 13. Segment A‐B, 800 MHz antenna, 2008.

Figure 14. Segment A‐B, 800 MHz antenna, 2009.

ASSESSMENT OF THE CONSERVATION STATE OF AN HISTORIC BUILDING BY GPR

e‐conservation 61

Bibliography

[1] L. B. Conyers and D. Goodman, Ground Penet‐

rating Radar: an Introduction for Archaeologists,

AltaMira Press, Walnut Creek, London and New

Delhi, 1997

[2] D. J. Daniels (ed.), Ground Penetrating Radar,

The Institution of Engineering and Technology,

London, 2007

[3] F. García García, M. Ramírez Blanco, I.l Rodríguez

Abad, R. Martínez Sala, I. Tort Ausina, J. Benlloch

Marco, and J. L. Montalvá Conesa, “GPR technique

as a tool for cultural heritage restoration: San Miguel

de los Reyes Hieronymite Monastery, 16th century

(Valencia, Spain)”, Journal of Cultural Heritage, Vol‐

ume 8 (1), 2007, pp. 87‐92, doi:10.1016/j.culher.

2006.10.005, URL

[4] V. Pérez‐Gracia, F. García, L. G. Pujades, R. Gon‐

zález Drigo, and D. Di Capua, “GPR survey to study

the restoration of a Roman monument”, Journal of

Cultural Heritage, Volume 9 (1), 2008, pp. 89‐96,

the validity of the measurements. The differences

between the 2008 and 2009 results are obvious.

At the depth of about 1–1,4 m are highlighted

the reflections of the electromagnetic radiation

received from the intervention over the founda‐

tion with concrete. This intervention was made to

consolidate the porch and the wall façade corres‐

ponding to the main entrance.

Even if the scanned area does not correspond pre‐

cisely to the place where the intervention was

made, the reflections are present because the

electromagnetic radiation is propagated in the

soil under the form of a truncated cone. That ex‐

plains why those reflections are present in 2009

– otherwise under the strict area of the house,

delimited by exterior walls, the interventions

concerned just a superficial depth.

Conclusions

We have obtained a high accuracy examination by

nondestructive means of the Ruşeţu house foun.‐‐

dation at the Village National Museum “Dimitrie

Guşti” in Bucharest, Romania.

The results highlighted the anomalies of the un‐

derlayers in a mapping format that also provided

the depths at which they could be found.

A fast and efficient acquisition model was applied

using two different frequency antennas (500 and

800 MHz). The information was processed and

collected in a dedicated database elaborated for

long term monitorization.

The differences between the recordings performed

in 2008 and 2009 revealed an existent interven‐

tion. This involved the consolidation of the entire

perimeter of the construction with concrete.

Proofs of this intervention have been identified

by the 2009 scan at a depth ranging between

1 m and 1.4 m. These data were not present in the

2008 research.

Periodic data acquisition obtained according to

the procedure proposed will determine an ac‐

curate characterization and comparison of the

collected results.

Acknowledgements

The author would like to acknowledge the support

of his coordinator Roxana Rădvan and colleague

Dragoş Ene from the National Institute for Deve‐

lopment and Research in Optoelectronics INOE

2000. Also a special thank is addressed to Vivian

Dragomir, from the Village National Museum

“Dimitrie Guşti”, Bucharest.

62 e‐conservation

LUCIAN CRISTIAN RATOIU

doi:10.1016/j.culher.2007.09.003, URL

[5] D. Barilaro, C. Branca, S. Gresta, S. Imposa, A.

Leone, and D. Majolino, “Ground penetrating radar

(G.P.R.) surveys applied to the research of crypts

in San Sebastiano's church in Catania (Sicily)”,

Journal of Cultural Heritage, Volume 8 (1), 2007,

pp. 73‐76, doi:10.1016/j.culher.2006.10.003, URL

[6] S. Castellaro S. Imposa, F. Barone, F. Chiavetta,

S. Gresta, and F. Mulargia “Georadar and passive

seismic survey in the Roman Amphitheatre of Catania

(Sicily)”, Journal of Cultural Heritage, Volume 9(4),

2008, pp. 357‐366, doi:10.1016/j.culher.2008.03.

.004, URL

[7] F. Soldovieri, and L. Orlando, “Novel tomographic

based approach and processing strategies for GPR

measurements using multifrequency antennas”,

Journal of Cultural Heritage, Volume 10, Supple‐

ment 1, ICT and Remote sensing for Cultural Resource

Management and Documentation, 2009, pp. 83‐92,

doi:10.1016/j.culher.2009.09.001, URL

[8] P. X. Neto, and W. E. de Medeiros, “A practical

approach to correct attenuation effects in GPR

data”, Journal of Applied Geophysics, Volume 59

(2), 2006, pp. 140– 151, doi:10.1016/j.jappgeo.

2005.09.002, URL

LUCIAN CRISTIAN RATOIUConservator‐restorer

Contact: [email protected]

Lucian Cristian Ratoiu is a conservator‐restorer

specialized in mural paintings. He graduated in

2007 from the Department for Conservation‐Res‐

toration Works of Art of the National University

of Art in Bucharest, Romania. Since 2008, he is

working as an assistant researcher at the Centre

of Excellence for Restoration by Optoelectrical

Techniques of the National Institute for Develop‐

ment and Research in Optoelectronics INOE.

CALL FOR SUBMISSIONS

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of articles on a wide range of relevant topics

for the cultural heritage sector.

Next deadlines for article submission are:

for Issue 19, April 2011 – submissions due

1st March 2011

for Issue 20, June 2011 – submissions due

1st May 2011

Nevertheless, you can always submit your

manuscript when it is ready. Between the

receival of the manuscript until the final

publication may pass up to 3 months

according with:

‐ the number of the manuscripts on hold,

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‐ the pre‐allocated space in the magazine

to each section

Please check our publication guidelines

for more information.

e‐conservation 63

ASSESSMENT OF THE CONSERVATION STATE OF AN HISTORIC BUILDING BY GPR

case

stud

y

Virtual reconstruction of the polychromy was chosen to pre‐

serve the artistic authenticity of the sculptures “Evangelist”

and “Madonna and Child”, producing variants of virtual

chromatic integration that are aimed at creating images in‐

dicative of the original appearance of the objects. Represent‐

ations of this type come as a manifestation of a mental

exercise to view complete polychrome sculptures, or their ap‐

pearance after chromatic integration, with the advantage that

there is no direct intervention on the objects. Virtual restora‐

tion of the polychromy can be achieved in several ways, de‐

pending on options such as image editing technical skills

and available software.

VIRTUAL AESTHETIC PRESENTATIONOF POLYCHROME SCULPTURES

By Daniela Cristina Pintilie

Preserving the artistic authenticityof polychrome carved wood piecesin the conservation‐restoration process

Figures 1 and 2.“Evangelist” polychrome sculpture.

e‐conservation

Introduction

Each work of art, regardless of its execution tech‐

nique, dating or conservation state, requires a

thorough analysis prior to any intervention. It is

absolutely necessary to know the historical con‐

text of objects in the restoration process and the

possibility to compare them with similar objects

when they are in advanced state of decay, in order

to avoid a hypothetical undesirable restoration and

its consequences. Every possible intervention must

be treated critically to preserve the artistic authen‐

ticity of the object, being very important to avoid

any operations that are not necessarily required.

In this article two case studies are on display, two

conservation‐restoration proposals that include

chromatic integration and polychromy virtual re‐

construction. The reconstructions made using

software are not aimed at creating models of the

objects, or their possible aspects after interven‐

tion, but are intended to achieve virtual images

of the undamaged sculptures. Until recently, but

even today, polychromy reconstruction has been

performed directly on objects, either by repainting

–intervention that has affected the authenticity

of the sculptures, or by the complete reproduction

of the object, operation that is similar to the vir‐

tual reconstruction.

VIRTUAL AESTHETIC PRESENTATION OF POLYCHROME SCULPTURES

65

Figures 3 and 4. Stratigraphy at the level of the garment:a. support of wood; b. original primer; c. green; d. blue;e. repainting primer; f. green – repainting.

66 e‐conservation

I. Case Study:“Evangelist” Polychrome Sculpture

The Evangelist sculpture has been dated back to

the early eighteenth century, having Transylvania

as its place of origin. Today it belongs to a private

collection. It has 63 cm height, 24 cm width and

a thickness varying between 3.3 and 12.5 cm. It

was executed in weak tempera on carved wooden

support. The sculpture is a bas‐relief that was part

of an overall frieze type, probably from a shrine.

In time, the sculpture has been subjected to some

interventions at the level of the paint layer, mainly

repaintings that are visible in the area of the green

garment. Different layers could be identified as:

green whitened with primer, blue whitened with

primer and a final layer of green. Given that the

layers of repainting are powdery and the original

is not, it is supposed that for their execution in‐

compatible materials were used or the binder was

applied in insufficient concentration.

Preserving the artistic authenticity of sculpture

For the virtual reconstruction of the Evangelist

polychrome sculpture photographs acquired by

optical microscopy were used, of samples taken

from areas where the painting was preserved.

Virtual restoration of the polychromy of theEvangelist sculpture

L*a*b* parameters of the pigments were deter‐

mined using Adobe Photoshop, using photos

taken from optical microscope Leica DMLS from

the laboratory of Chemistry of the Conservation

and Restoration Department of the National Art

University, Bucharest. For each color five meas‐

urements from different points were recorded in

order to obtain values as close as possible to the

reality.

Figure 5. Map of the sampling areas.

CRISTINA‐DANIELA PINTILIE

e‐conservation 67

The average of the parameters obtained from the

five points was calculated and used as standard

for the subsequent mathematical calculations to

determine the ∆E* (total difference), made in

Microsoft Excel®. (∆E *= √ (∆ L* a* 2 + ∆ 2 + ∆ b*

20). Once determined, values greater than 10 ∆E*

were excluded and the average was recalculated

resulting in the determination of the local color

parameters. The same calculations were repeated

for each color.

L* represents brightness, a* chromatic parameters

on the Magenta – Green axis, b* chromatic para‐

meters on the Yellow‐Blue axis, C* chromatic in‐

dex,∆C* total color difference, H* is the hue angle,

∆H* hue angle range. ∆* values indicate how much

the L*a*b* parameters differ from the standard

and the analyzed values. The objective is to obtain

a color space for classifying numerical differences.

A* and b* parameters are independent of the

brightness L*, expressing only color differences,

namely: if a* is greater, it means that the sample

has more red than the standard, or more green if

a* is lower; a greater b* value shows that the sam‐

ple is more yellow, or more blue for a lower b*

value; and finally when L* is greater, the sample

is lighter than the standard, and darker for a lower

L* value.

Starting with the garment stratigraphy, where the

sequence of the layers it is best revealed, three

possible aspects of the object at a certain point

during time were virtually generated with Adobe

Photoshop. Thus, an image of the complete poly‐

chromy of the object was obtained without inter‐

fering with it. After the calculations, the results

were illustrated through graphic representations.

Determination of the L*a*b* values for red

(garment)

The points in which the L*a*b* parameters were

recorded on the optical microscopy photography

were marked with R (R1, R2, R3, R4, R5). For R2

and R3, ∆E* is greater than 10, therefore, the

corresponding L*a* b* values were excluded and

the average was recalculated from the remaining

values (figure 6).

Determination of the L*a*b* values for ocher

The points in which the L*a*b* parameters were

recorded were marked with C (C1, C2, C3, C4, C5).

To achieve the final average, i.e., to establish the

L*a* b* parameters of the carnation, measure‐

ments from points C1 and C5 with ∆E* greater

than 10 were eliminated (figure 7).

Figure 6. Determination of the L*a*b* values for red (garment). Figure 7. Determination of the L*a*b* values for ocher.

VIRTUAL AESTHETIC PRESENTATION OF POLYCHROME SCULPTURES

68 e‐conservation

Determination of the L*a*b* values for gray (book)

The points in which the L*a*b* parameters were

recorded were marked with G (G1, G2, G3, G4, G5).

All measureºments have ∆E* value within the ac‐

cepted parameters, so all were used to calculate

the final average (figure 8).

Determination of the L*a*b* values for whitened

green

The points in which the L*a*b* parameters were

recorded were marked with VA (VA1, VA2, VA3, VA4,

VA5). ∆E* value for VA1 was greater than the limit

so it was eliminated (figure 9).

Determination of the L*a*b* values for blue

The points in which the L*a*b* parameters were

recorded were marked with A. ∆E values greater

for the L*a*b* parameters of the points A2, A4

and A5, so the final average was recalculated us‐

ing the remaining ones (figure 10).

Determination of the L*a*b* values for green

(garment)

The points in which the L*a*b* parameters were

recorded were marked with V (V1, V2, V3, V4, V5).

Having a value greater than 10, the point V3 was

removed in order to achieve the average of the para‐

meters L*a*b* corresponding to green (figure 11).

Given the garment stratigraphy and the L*a*b*

values obtained we were able to achieve three

possible aspects that the object might have had

during the past. The layers of repaintings are well

distinguished, as follows: whitened green, azur‐

ite blue, green.

Figures 8‐11 (from up to down).Determination of the L*a*b* values for gray (book);

whitened green; blue; and green (garment).

e‐conservatione‐conservation

CRISTINA‐DANIELA PINTILIE

From up to down,left to right:

Figure 12. Evangelistsculpture after virtual,partial polychromy res‐toration.

Figure 13. EvangelistSculpture after virtualpolychromy restoration ‐whitened green.

Figure 14. EvangelistSculpture after virtualpolychromy restoration– blue.

Figure 15. EvangelistSculpture after virtualpolychromy restoration– green.

e‐conservation 69

VIRTUAL AESTHETIC PRESENTATION OF POLYCHROME SCULPTURES

70 e‐conservation

Virtual chromatic integration of the Evangelistsculpture

In order to preserve the artistic authenticity of the

object without interfering with it, two possible

aspects were obtained after chromatic integration

carried out in velatura technique only on the ori‐

ginal, visible ground layer.

This operation allows the artistic authenticity to

be preserved by minimal intervention on the ob‐

ject, placing instead more emphasis on its con‐

servation.

As with the virtual reconstructions of the poly‐

chromy, digital chromatic integration does not

intend to achieve variants from which to choose

the most appropriate, but only to satisfy the de‐

sire to visualize the outcome of an intervention

of this type.

Archaeological restoration is justified by the fact

that the polychromy is preserved only in a very

small percentage, from which a certain propor‐

tion is repainting.

Chromatic integration trials made directly on the

object are not 100% reversible, affecting the ori‐

ginal to some extent. Removal of tests inevitably

damages part of the original matter, either the pla‐

ster or the paint layer, affecting thus the authen‐

ticity of the object. The risk of damaging the sculp‐

ture through interventions that are not necessarily

required is very high and is not justified, especially

since its conservation does not depend on them.

Although the proposed treatment is based on an

archaeological approach, two versions of virtual

chromatic integration have been achieved with

an image editing software in order to emphasize

that this operation is not absolutely necessary.

Figures 16‐18. Left: original aspect of the Evangelist sculpture; Center: a first variant of virtual chromatic integration;Right: a second variant of virtual chromatic integration.

CRISTINA‐DANIELA PINTILIE

Figure 19. Polychrome sculpture Madonna and Child.

e‐conservation 71

II. Case Study:Madonna and Child Polychrome Sculpture

The sculpture Madonna and Child dates from the

twentieth century and is also originally from Tran‐

sylvania. Today it belongs to a private collection.

It was executed in tempera on carbonized wood

support, which is visible at the naked eye inside

the lacunas of the pictorial layer. No repaintings

were identified on this sculpture.

Conservation state

The wood was carbonized before the execution of

the polychromy, which leads to the assumption

that the sculpture is a fake and that the support

was burned so that the polychromy deteriorates

in a short time. The carbonized surface transpires

through the preparation and color layers, creating

the impression of an antique.

The assessment of the conservation state at the

level of the wood support shows carbonizations,

lacunas on large areas and surface deposits. The

pictorial layer is friable and has a poor adherence

to the substrate, showing erosions, lacunas, de‐

posits and stains.

Figure 21. Madonna image: a ‐ stains due to carbonized woodsupport; b ‐ erosion of color layer; c – lacunas of the color lay‐er up to the preparation layer; d – lacunas of the preparationlayer up to the wood support.

Figure 20. Stratigraphy in the garment: a ‐ wood support;b ‐ carbonized wood support; c – preparation layer; d ‐ firstcolor layer ‐ red; e ‐ second color layer ‐ blue.

VIRTUAL AESTHETIC PRESENTATION OF POLYCHROME SCULPTURES

72 e‐conservatione‐conservation

Preserving the artistic authenticity of thepolychrome sculpture Madonna and Child

When dealing with a fake, the issue of authenti‐

city is different to some degree. On the one hand,

there is the issue of preserving the authenticity

of a work normally done in tempera on wood tech‐

nique, and on the other hand, preserving the au‐

thenticity as it was thought by its author, through

the carbonization of the wood and the creation

of a false patina. Given these circumstances, the

fairest solution to the object and to the author's

intention is to adopt an archaeological approach

to its restoration.

Operations performed directly on the object

From the methodological point of view a resto‐

ration that includes minimal interventions was

chosen. Light surface deposits were removed

with a soft brush, after which the pictorial layer

was consolidated in several stages with fish glue

in different concentrations. The deposits present

on the painted surface, on the preparation layer

and on the wood visible inside the gaps were re‐

moved.

Virtual restoration of the polychromy of theMadonna with Child sculpture

The sculpture benefited from its integrity for a very

short period of time. There is also the possibility

that some gaps were induced deliberately by the

author. To get a picture of the sculpture as it could

have looked in the beginning, a polychromy vir‐

tual restoration was carried out.

Unlike in the case of the Evangelist sculpture, to

reconstitute the polychromy of this object several

particular issues must be taken into account, due

to its specific execution technique. The red color

and the carbonized wood surface that became

visible through the blue create the false antique

impression by darker or lighter areas. This gives

personality and authenticity to the sculpture.

Thus, we chose to restore the polychromy by mim‐

icking the existing areas using an image editing

software like Adobe® Photoshop®, method that

allowed us to keep the artificial antique effects.

Figure 22. Madonna and Child sculpture after virtual, partialpolychromy restoration.

CRISTINA‐DANIELA PINTILIE

e‐conservation 73

Figure 23. Madonna and Child sculpture after virtualpolychromy restoration.

e‐conservation

The virtual restoration of the polychromy is not

aimed at creating a model, or a sketch of what the

object could become if subject to possible inter‐

ventions, but stands for projecting a mental re‐

construction of what the sculpture would have

been immediately after its creation.

Virtual chromatic integration of the Madonnaand Child sculpture

Chromatic integration was carried out virtually by

applying a neutral glaze on the visible preparation

layer with the intention to send the gaps to the

background so that to create a surrounding for

the original existing painting. Given this and the

practical execution with reversible materials, namely

water colors, the restoration principles should be

respected, but one can not predict whether the

outcome will be satisfactory and beneficial for the

object. In this respect, virtual representations

bring a great contribution to the establishment

the methodology for restoration, especially the

treatment of the gaps.

As in the case of the Evangelist sculpture, we do

not aim to achieve chromatic integration versions

in order to select the best from them, but to be

able to visualize this option without interfering

with the authenticity of the object.

Even if we chose an archaeological restoration type,

all possible versions should be considered, since

at a future restoration, in a detrimental context

one might even opt for the repainting of the sculp‐

ture.

By virtual chromatic integration the author's in‐

tent to create an antique‐looking sculpture is re‐

spected and at the same time a coherent reading

of the sculpture is achieved.

Conclusions

The authenticity of the works of art is mainly pro‐

tected by minimal intervention especially during

restoration, but this does not mean that the doc‐

umentation of the object should also be limited.

Whether it is decided to remove or not the re‐

paintings, this aspect must be documented by

VIRTUAL AESTHETIC PRESENTATION OF POLYCHROME SCULPTURES

laboratory analyses, cross‐sections, etc., which

eventually will be part of the file that accompanies

the object and can serve for a future restoration.

Unfortunately, virtual representations are not al‐

ways well received, and their purpose may be mis‐

interpreted. It is true that they can serve as a range

of possible options to a reconstitution, repainting,

restoration or chromatic integration, but their

value in the preservation of artistic authenticity

should not be neglected.

If until recently the only possibilities to materialize

a reconstructed image of a work of art, or of an

architectural ensemble, of which some elements

are missing or have lost polychromy during time,

Figures 24 and 25. Madonna and Child sculpture before and after virtual chromatic integration.

CRISTINA‐DANIELA PINTILIE

74 e‐conservatione‐conservation

DANIELA‐CRISTINA PINTILIEConservator‐restorer

Contact: [email protected]

Daniela‐Cristina Pintilie is a conservator‐restorer

specialised in panel paintings. She graduated in

2008 from the Faculty of Art History and Theory,

Conservation and Restoration section, of the Na‐

tional University of Arts in Bucharest, Romania

where she also completed a Master degree in 2010.

During her training, she participated in different

conservation projects such as of the wooden Church

of the Nativity of the Virgin from Ieud, Maramures,

the Romanian Athenaeum, and the churches Col­ţea, Stavropoleos and Doamnei in Bucharest, the

Beheading of St. John the Baptist from Arbore, and

St. Nicholas from Bălineşti. She currently works

for a private conservation company in Bucharest.

were repaintings or reproductions, now we can

perform virtual representations, which not only

do not affect in any way the original, but are more

accurate, involve lower costs, require fewer con‐

sumption of materials, and the diversity of treat‐

ment of various aspects is greater.

Polychromy virtual restoration can be achieved

in several ways, where possible, as could be ob‐

served in this study. It can be precise, as in the

case of the Evangelist sculpture, for which values

L*a*b* were determined, or intuitive as in the

case of the Madonna and Child sculpture. Both

versions are useful, and during the course of an

intervention the second may be preceded by the

first one. Such representations can protect works

of art from operations that might compromise

their authenticity and integrity. No operation

performed directly on the object, be it cleaning

tests or chromatic integration proposals, is fully

reversible.

To preserve the artistic authenticity of an object

every intervention must be treated critically, and

it is very important to avoid any operations that

are not necessarily required.

Note

The present article is an extract from author’s

dissertation work with a major specialization ‐

artistic heritage conservation and restoration

methodologies: "Protecting the artistic authen‐

ticity of polychrome carved wood pieces in the

process of conservation and restoration", carried

out within the Department of Conservation and

Restoration, National University of Arts – Bucha‐

rest. The author graduated in June 2010 under

the coordination of Lect. univ. Dana LuminiţaPostolache – conservator‐restorer, Lect. univ.

Olimpia Hinamatsuri Barbu and Prof. univ. Ioana

Gomoiu, conservation‐scientists.

Selected bibliography

[1] C. Brandi, Theory of restoration, Istituto Centraleper il Restauro/Nardini Editore, 2005

[2] O. Cassaza, Il restauro pittorico‐ nell'unita di meto‐dologia, Nardini editore, 2007

[3] R. Peral, D. Sagasti and S. Sillaurren, "Virtual Re‐storation of Cultural Heritage Through Real‐Time 3DModels Projection", in M. Mudge, N. Ryan, and R. Sco‐pigno (eds.), VAST 2005, The 6th International Sym‐posium on Virtual Reality, Archaeology and CulturalHeritage, Oct 30‐Nov 4, 2006, Pisa, Italy, URL [pdf]

[4] F. Descamps, and J. Carballo (eds), Methodology forthe Conservation of Polychromed Wooden Altarpieces,Junta de Andalucía, Consejería de Cultura and the J. PaulGetty Trust, 2006, URL [pdf]

[5] G. López, M. José, and F. Descamps (eds.), Workshopon Methodology for the Conservation of PolychromedWooden Altarpieces: Document on Retablos 2002, TheGetty Conservation Institute and Junta Andalucía Con‐sejería de Cultura, 2004, URL [pdf]

VIRTUAL AESTHETIC PRESENTATION OF POLYCHROME SCULPTURES

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No. 18, February 2011

ISSN: 1646‐9283

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