Oswald Lohse Historical Photographic Wide-Field Survey:Camera Replica Milcho K. Tsvetkov 1, Gotthard Richter 2, Klaus Staubermann 3, Svetlin Fotev 4, Ivan.

Oswald Lohse Historical Oswald Lohse Historical Photographic Wide-Field Photographic Wide-Field Survey:Camera Replica Survey:Camera Replica

Milcho K. Tsvetkov1 , Gotthard Richter2,

Klaus Staubermann3 , Svetlin Fotev4 , Ivan Parov5 Petra Boehm2, Katya Tsvetkova1

1) Institute of Astronomy, Bulgarian Academy of Sciences

2) Astrophysicalishes Insitute Potsdam, Germany

3) Utrecht University, University Museum, The Netherlands

4) Space Research Institute, Bulgarian Academy of Sciences

5) Department of Astronomy,Sofia University, BulgariaJuly, 2004

1. Introduction• WFPDB

2. Lohse Plate Archives re-discovery3. Including of the Plate Archive in WFPDB4. Lohse Plate Digitization5. Lohse Photographic Camera6. Replica

• Sources and Publications• Drawings• Preparing of the Replica• Test at the Sofia Observatory• Plates• Future Plans

IntroductionIntroductionWide-Filed Plate DatabaseWide-Filed Plate Database

WFPDB Project Goals – Developed as a project of the IAU WG WFI, started in 1991 at the IAU GA,

WG WFI Chairman Richard West and WGSS IAU Commission 9.

Supported by: Bulgarian NSF 1993-2001: F-311, 340, 650 I-529, 1103,

Alexander von Humboldt Foundation, Center for Informatics, Muenster University, German Research Council (DFG), COST A283.

Main Directions:– Catalog of WFPA: 345, 2.2x106 plates

– Plate logs transformation - 700 000 plates

– Search in WFPDB: http://www.skyarchive.org/search

– Plate digitization: Epson 1640XL, PDS1010plus

IntroductionIntroductionWide-Filed Plate DatabaseWide-Filed Plate Database

Website:http://www.skyarchive.org

More WFPDB Descriptions:More WFPDB Descriptions:

FOR MORE INFO...

Website:http://www.skyarchive.org

Potsdam plate archives: Potsdam plate archives: WFPDB incorporation: WFPDB incorporation:

The Astrophysical Institute Potsdam wide-field plate collection consists of 12 plate archives obtained in the period 1879 - 1970 (see Catalogue of Wide-Field Plate Archives, version 5.0, March 2004, http://www.skyarchive.org) with more than 10 000 plates and films stored not only in Potsdam but in Leiden and Sonneberg, too. The plates contain valuable astronomical information easily to be retrieved. The Potsdam wide-field plate collection reflects also the history and development of the Potsdam Observatory

The accumulated wide-field photographic observations in the Astrophysical Institute Potsdam (AIP) have well known contributions to astronomy, but also to the development of photography itself. Such are the contributions of many observers from Potsdam, e.g. O. Lohse (since the foundation of the observatory), J. Scheiner (the end of 19th century), J. Hartmann (the beginning of 20th century), E. Hertzsprung and K. Schwarzschild (the 10s of 20th century), G. Eberhard (the 20s - 30s of 20th century). Another aspect of this development is that practically the Potsdam Observatory was the base for testing of new astronomical emulsions, beginning with the dry photographic plates of Schleussner (fabric in Frankfurt) to AGFA Enterprise up to 1960 and ORWO after 1960.

The process of archiving of the wide-field photographic observations comprises such steps as making of an inventory of the plate collection, preparation of computer-readable versions of the plate catalogues, plate digitization and providing of good storage with suitable temperature, humidity free conditions and easy access to the plates and to the plate digitized information.

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Potsdam plate archives: Potsdam plate archives: WFPDB incorporation: WFPDB incorporation:

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The Lohse Plate ArchivesThe Lohse Plate Archives

The LOHSE archives contain observations since 1879. According to the found Lohse's logbook 217 plates are obtained with the refractor with diameter 30 cm, focal length 5.4 m, and scale 38"/mm. The manufacturer of the optics was H. Schroeder and for the mechanics - A. Repsold. This refractor was called "the Great Refractor" in the period 1879-1899 (after 1899 the name "Great Refractor" was ascribed to the new 80 cm refractor, then put in operation). Since 1888 Lohse sometimes mounted on the refractor two heliographic objectives with a diameter 0.13 cm (the first one with focal length 2.10 m, scale 98 "/mm, and the second one with focal length 1.36 m, scale 152 "/mm, and field size 5, Tsvetkov et al. 1999. Astron. Nachr., 320).

Wilhelm Oswald Lohse (1845 1915)

The Lohse Plate Archives: The Lohse Plate Archives: RediscoveryRediscovery

The AIP Great RefractorDome of the Great Refractor

The Lohse Plate Archives: The Lohse Plate Archives: RediscoveryRediscovery

• The Lohse plates were re-discovered in 1998 in a small room on the 2nd floor of the dome of the Great refractor in Telegrafenberg. - 6 boxes, plate with size of 9x12 cm

•The logbooks were accompanied with two blocknotes.

• At present they are stored under special conditions at the AIP library

The Lohse Plate Archives: The Lohse Plate Archives: AnalysisAnalysis

• 67 plates of the archives, taken with the greatest instrument of Potsdam in the period March 1885 February 1889.

• from 217 plates, listed in his logbook, the first 148 from 1879 to 1885 are not found.

One Lohse’s focus plate

The Lohse Plate Archives: The Lohse Plate Archives: AnalysisAnalysis

Number of the platesvs.

fields observed

The Lohse Plate Archives: The Lohse Plate Archives: DigitizationDigitization

10 of the Lohse's plates have been chosen for digitalization with the PDS 2020 GM + microdensitometer of Muenster

University in July 1998. The standard square diaphragm of 10 microns and a step size of 10 microns was used.

Table 4 summarizes the scanning parameters and results.

The measurements of 12 stars in B light from the photometric sequence of Andrews (1970) in Orion nebula

(M42) show an average photographic photometry deviation

of oe = 0:13 m (Fig. 4). In Fig. 4. and Fig. 5. the

pictures of the stellar cluster h Persei (NGC 884) and Orion nebula (M42/M43) processed from the original Lohse's

plate scans (LS 171, LS 213) with MIDAS are shown.

LS. No. 213, M42

The Lohse Plate Archives: The Lohse Plate Archives: DigitizationDigitization

h Persei

M42-43, ORION

The Lohse Photographic camera:The Lohse Photographic camera:sources and publication sources and publication

Publications:First professional photographic

camera in the world

Potsdam Observatory library Konkoly Observatory libraryNecessary better copies with

details!

The Lohse Photographic cameraThe Lohse Photographic camerapictures (cont.) pictures (cont.)

Drawing Drawing The Lohse Photographic camera The Lohse Photographic camera

Svetlin Fotev, © SSADC,

Eng. Svetlin Fotev

Drawing Drawing The Lohse Photographic camera The Lohse Photographic camera

Svetlin Fotev, © SSADC

The Lohse Photographic cameraThe Lohse Photographic cameraReplica Replica

The Lohse Photographic camera The Lohse Photographic camera ReplicaReplica

Eng. Ivan Parov

The Lohse Photographic camera The Lohse Photographic camera ReplicaReplica:: Test at the Grubb refractor of Test at the Grubb refractor of

the Sofa University Observatorythe Sofa University Observatory

Searching a suitable telescope at the Balkan observatories to attach and test the replica.

Sites tested: Belgrade, Bucharest, Konkoly, Sombathely, Sofia.

Result: the best place for the test is the Sofia University Observatory with the 18 cm refractor (100 years old).

The Uni-Sofia Observatory

18 cm Grubb Refractor

The Lohse Photographic Camera The Lohse Photographic Camera ReplicaReplica:: Test at the Grubb refractor of Test at the Grubb refractor of

the Sofa University Observatorythe Sofa University Observatory

Dome of the Grubb Refractor

The Lohse Photographic Camera The Lohse Photographic Camera ReplicaReplica:: Test at the Grub refractor of Test at the Grub refractor of

the Sofa University Observatorythe Sofa University Observatory

The Lohse Photographic camera The Lohse Photographic camera Plates usedPlates used

Lohse used mainly the Dr. Schleussner plates with size of 9x12 cm.

The Lohse Photographic CameraThe Lohse Photographic CameraPlate Used Plate Used

Preparing the plates according to the Gaedike technologyfrom 19 century and used them to repeat the Lohse observations.The plates were prepared by Prof. Tsveta Petrovafrom the Central Laboratory for Optical Recording of the Information at the Bulgarian Academy of Sciences.

The Lohse Photographic Camera The Lohse Photographic Camera

Prof. Tsveta PetrovaCLOSOI, BAS

Photolaboratory atthe Uni-Sofia Observatory

The Petrova’s samples of the Geadike type emulsion plates

The Lohse Photographic Camera:The Lohse Photographic Camera:Future PlansFuture Plans

Preparing a copy from the replica for AIP (grant needed)

Repeating the Lohse observations

Incorporation the Lohse plate scans in the WFPDB

AcknowledgementsAcknowledgements

The Lohse Camera Replica was realized with the grant provided by Dr. Klaus Staubermann and the enthusiasm

of the staff of Sofia Sky Archive Data Center and Sofia University Observatory.

We are thankful to Prof. G. Ivanov providing us with the Grubb telescope of the Sofia University Observatory.

In particular the incorporation of Lohse photographic observations was supported by the DFG/BAS grant

BUL436/1999

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