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itute for Conservation of shington, DC 20005. (202) ndividual authors retain
merican Institute for
by the Photographic rvation of Historic & Artistic aterials Group, Topics in presented at PMG meetings isciplines.
ol. 2, have not undergone a s and materials described t be considered official division of the AIC but does
THE ACETATE NEGATIVE SURVEY: FINAL REPORT
D a v i d H o r v a t h , C u r a t o r , U n i v e r s i t y o f L o u i s v i l l e P h o t o g r a p h i c A r c h i v e s
( T h e f o l l o w i n g t a l k a n d i l l u s t r a t i o n s were e x c e r p t e d from a w r i t t e n r e p o r t of t h e same t i t l e w h i c h is a v a i l a b l e f r o m t h e U n i v e r s i t y o f L o u i s v i l l e P h o t o g r a p h i c A r c h i v e s . )
T h o s e o f y o u who were i n L o u i s v i l l e i n 1984 when o u r W i n t e r
M e e t i n g w a s h e l d a t t h e P h o t o g r a p h i c A r c h i v e s may r e c a l l t h a t t h e
t i t l e o f my t a l k t h e r e w a s " A N i g h t m a r e i n My C l o s e t . " I n i t I
d e s c r i b e d t h e e f f o r t s w e were m a k i n g t o m o n i t o r a n d d e t e r m i n e t h e
e x t e n t o f t h e d e t e r i o r a t i o n o f o u r own a c e t a t e n e g a t i v e f i l e s .
The l a s t s e v e r a l y e a r s I h a v e l e a r n e d a l o t more a b o u t a c e t a t e
f i l m a n d I h a v e j u s t completed a N a t i o n a l Museum A c t f u n d e d
p r o j e c t t o s u r v e y c o l l e c t i o n s a t o t h e r i n s t i t u t i o n s a s w e l l . So
now I c a n c a l l t h i s t a l k "A N i g h t m a r e i n T h e i r C lose t s . "
I n p r e s e n t i n g t h e r e s u l t s o f my w o r k , I w i l l t a l k more t o d a y
a b o u t t h e m e t h o d o l o g y o f t h e s t u d y , t h e c o m p i l a t i o n o f r e s u l t s ,
a n d my c o n c l u s i o n s , r a t h e r t h a n t h e h i s t o r i c a l r e s e a r c h o r
r e s u l t s of my l i t e r a t u r e s e a r c h . T h e s e a reas a re d i s c u s s e d i n
d e t a i l i n The Acetate N e g a t i v e S u r v e y : F i n a l Repor t .
. METHODOLOGY
The prime f o c u s o f t h i s s t u d y w a s a s u r v e y of f i l m
c o l l e c t i o n s a n d a d e t e r m i n a t i o n of t h e e x t e n t of c e l l u l o s e
acetate d g r a d a t i o n . I n s t i t u t i o n s were selected for t h e s u r v e y
based o n t h e i r h o l d i n g s o f n e g a t i v e s f r o m t h e p e r i o d 1925-1955.
C o l l e c t i o n s i n c l u d e d h a d a c c u r a t e d o c u m e n t a t i o n f o r t h e da tes of
25
p a r t i c u l a r n e g a t i v e s a v a i l a b l e e i t h e r d i r e c t l y o n t h e n e g a t i v e
s l e e v e s o r t h r o u g h t h e u s e o f i n d e x e s o r o t h e r f i n d i n g a i d s . A
v a r i e t y of c o l l e c t i o n s were i n c l u d e d i n t h e s a m p l i n g t o g e t t h e
b e s t p o s s i b l e v a r i e t y of f i l m t y p e s , u s e s , a n d f o r m a t s .
I n s t i t u t i o n s were a l s o se l ec t ed w h i c h p r e s e n t e d a v a r i e t y of
s t o r a g e a n d e n v i r o n m e n t a l c o n d i t i o n s .
The s i t e s u r v e y s t h e m s e l v e s c o n s i s t e d of two s t e p s . F i r s t ,
w o r k s h e e t s were completed f o r e a c h c o l l e c t i o n . E n t r i e s were made
o n t h e w o r k s h e e t s f o r n e g a t i v e s w h i c h f i t t h e p r o j e c t ' s
c h r o n o l o g y . S a m p l e s w e r e i n c l u d e d f o r b o t h d e g r a d e d a n d non-
d e g r a d e d e x a m p l e s a n d f o r a l l m a n u f a c t u r e r s a n d f i l m t y p e s
( n o t c h e s ) r e p r e s e n t e d . The t o t a l number o f s a m p l e s would v a r y
w i t h e a c h c o l l e c t i o n d e p e n d i n g o n t h e a r r a n g e m e n t o f t h e
n e g a t i v e s , t h e s i z e o f t h e c o l l e c t i o n , a n d t h e ease o f d a t i n g
p a r t i c u l a r samples.
T h e w o r k s h e e t c o n t a i n e d t h e f o l l o w i n g i tems o f d a t a :
COLLECTION/NEG # T h i s c o l u m n w a s u s e d t o r e c o r d a c o l l e c t i o n s p e c i f i c number f o r e a c h i n d i v i d u a l s a m p l e i n c l u d e d . A two t o f o u r l e t t e r p r e f i x d e s i g n a t i n g t h e i n s t i t u t i o n w a s i n c l u d e d w i t h t h e i n s t i t u t i o n ' s own n e g a t i v e n u m b e r ( l o c a t i o n ) ,
MANUFACTURER C NUMBER The m a n u f a c t u r e r o f a p a r t i c u l a r n e g a t i v e sample w a s r e c o r d e d h e r e w i t h a n y number t h a t appeared embossed i n t h e f i l m e d g e w i t h t h e m a n u f a c t u r e r ' s name, T h i s n u m b e r , referred t o a s t h e " m a c h i n e number, ' ' is g e n e r a l l y c o n s i d e r e d t o be t h e number of a p a r t i c u l a r n o t c h i n g m a c h i n e u s e d i n t h e f i n i s h i n g o f t h e f i l m . H i s t o r i c a l l y , t h e s e n u m b e r s h a v e b e e n u s e d b y v a r i o u s m a n u f a c t u r e r s t o f o l l o w t h e movement of raw f i l m s t o c k , o r t o i n d i c a t e t h e number o f a n i n s p e c t o r o f a p a r t i c u l a r f i l m b a t c h . More r e c e n t l y Kodak h a s u s e d t h e number t o i d e n t i f y t h e f i l m p r o d u c t i t s e l f .
NOTCH F i l m n o t c h codes are c u t s o n t h e e d g e s o f s h e e t f i l m t h a t c a n be u s e d t o i d e n t i f y t h e f i l m t y p e , as w e l l a s loca te t h e e m u l s i o n s i d e of t h e f i l m when f i l m h o l d e r s are loaded i n t h e dark. T h e sample ' s "NOTCH REFERENCE" ( s e e A p p e n d i x B) was recorded o r , i f n o t knownr t h e a c t u a l n o t c h
26
w a s c a r e f u l l y t raced i n p e n c i l . A n o t c h r e f e r e n c e wou ld t h e n l a t e r be a s s i g n e d .
NOTCH REFERENCE A u n i q u e a l p h a n u m e r i c d e s i g n a t i o n w a s a s s i g n e d t o e a c h n o t c h . F o r Kodak n e g a t i v e s t h i s r e f e r e n c e re fe rs t o K o d a k ' s own n o t c h d e s i g n a t i o n a s r eco rded b y t h e i r P a t e n t O f f i c e . T h i s w a s u s e f u l f o r t h e i r own records a n d k e e p i n g t r a c k of n o t c h u s a g e a n d c h r o n o l o g y . U n f o r t u n a t e l y , t h e s e r e c o r d s a re n o t a v a i l a b l e from o t h e r m a n u f a c t u r e r s . F o r t h e s e e x a m p l e s a n o t c h r e f e r e n c e d e s i g n a t i o n w a s a s s i g n e d f o r t h i s s u r v e y . A l i s t i n g of n o t c h r e f e r e n c e s is i n c l u d e d i n A p p e n d i x B.
LEVEL OF DETERIORATION E a c h n e g a t i v e w a s a s s i g n e d a number f r o m 1-6 d e s c r i b i n g i t s p h y s i c a l c o n d i t i o n a t t h e t i m e o f t h e s u r v e y . T h e s e s i x l e v e l s c a n be desc r ibed a s f o l l o w s :
L e v e l - 1-- No d e t e r i o r a t i o n : f l a t n e g a t i v e .
L e v e l 2 - - N e g a t i v e e x h i b i t s s l i g h t or moderate e d g e c u r l w i t h s m o o t h s u r f a c e s o n b o t h e m u l s i o n a n d base s i d e s . Edge c u r l is a l w a y s s y m m e t r i c a l o n t h e t w o o r f o u r s i d e s a f f e c t e d .
L e v e l 3--Smell; t h e n e g a t i v e smel l s d i s t i n c t l y of acetic-or b u t y r i c ac id . T h i s d e t e r m i n a t i o n is d i f f i c u l t t o make i f t h e r e are l a r g e n u m b e r s of d e g r a d e d n e g a t i v e s i n a c o n f i n e d area s u c h a s a box o r drawer w h e r e t h e ac id odor permeates. U s u a l l y i n t h e s e cases t h e r e is l e v e l 4-6 d e g r a d a t i o n e v i d e n t as w e l l .
Leve l 4--Warpage; wavy p o r t i o n s i n edges a n d s u r f a c e of t h e n e g a t i v e ; n o t s y m m e t r i c a l ; no s e p a r a t i o n of e m u l s i o n o r base. One of t h e f i r s t s i g n s t h a t a n e g a t i v e may be d e g r a d i n g is t h a t it w i l l s h o w s i g n s of warpage. S l i g h t w a r p a g e o r d e f o r m a t i o n c a n a l s o be c a u s e d by t h e u n e v e n l o s s o f s o l v e n t s from t h e n e g a t i v e . The t y p e of warpage w h i c h i n d i c a t e s s e r i o u s d e g r a d a t i o n is most o f t e n v e r i f i e d by t h e e x i s t e n c e o f o t h e r f u r t h e r degraded samples i n t h e immediate v i c i n i t y of t h e warped n e g a t i v e .
Leve l 5 - -Bubb les : o c c a s i o n a l l y when a n ace ta te n e g a t i v e d e g r a d e s , b u b b l e s may f o r m b e t w e e n t h e e m u l s i o n a n d base o r b e t w e e n t h e base a n d t h e a n t i - c u r l b a c k i n g of t h e f i l m , T h e s e b u b b l e s v a r y i n s i z e a n d may appear i n a c i r c u l a r p a t t e r n from t h e c e n t e r of t h e n e g a t i v e o u t t o t h e e d g e s , O c c a s i o n a l l y t h e s e b u b b l e s a r e f i l l e d w i t h a v o l a t i l e l i q u i d .
L e v e l 6 - - S e p a r a t i o n of t h e e m u l s i o n , base, a n d a n t i - c u r l lzyers. T h i s c a n be e v i d e n t i n v a r y i n g degrees, f r o m s l i g h t l o c a l i z e d s e p a r a t i o n t o mass ive s e p a r a t i o n . A w h i t e c r y s t a l l i n e e x u d a t e is o f t e n s e e n u n d e r t h e
27
separated portions of the base material. This substance is most likely to be the plasticizer used to manufacture the film base such as tripheno1 phosphate.
DATE This column was used to record the date of the negative as closely as it can be determined from the photographer's records. TO be included in the final data analysis, the date should be reasonably verifiable within a year.
FILM T H I C K N E S S Initially the thickness of each negative sample was recorded using a dial type calipers. Little variation was noted between the sheet film negatives in various conditions, with thicknesses ranging from .008 to .010 inches in all samples in various conditions. After several site surveys this measurement was discontinued.
FILM S I Z E The nominal size of the sheet film being sampled.
NOTES Observations were recorded here for any special conditions of a particular sample, including additional comments about condition, appearance, or environment, as well as qualifications for date or notch information.
The second portion of the site or institutional surveys
consisted of an interview with the curator or caretaker of the
collection to record the storage and environmental history of the
material surveyed. This information would include, if known, how
and where the negatives were stored before they arrived at the
institution and the same information for the institution's own
storage. Of particular interest would be any trauma the
collection may have suffered, such as fire, flood, or warehouse
storage, that would effect the present condition of the
negatives .
COMPILATION OF RESULTS
Sixteen institutions were surveyed. Twenty-nine individual
collections were inspected and a total of 3396 negatives were
sampled, Only safety-based sheet film was sampled for this
project. Most of the negatives surveyed were considered
28
" p r o f e s s i o n a l " o r " p o r t r a i t " f i l m s a n d f e w g r a p h i c s a r t s t y p e
f i l m s were e n c o u n t e r e d . Aer ia l a n d o t h e r r o l l f i l m s t o c k were
n o t i n c l u d e d .
The e a r l i e s t d a t e d Kodak s a f e t y f i l m w a s 1 9 2 6 . Agfa s a f e t y
f i l m s a m p l e s d a t e d from 1936. D e f e n d e r s a f e t y f i l m d a t e d from
1934-1945 a n d D u p o n t D e f e n d e r from 1945-1955. O n l y s e v e r a l
samples f r o m t h e H a m m e r Company w e r e e n c o u n t e r e d a n d t h e s e d a t e d
f r o m 1946-48 .
A n o t c h b y n o t c h c o m p a r i s o n i s i n c l u d e d i n t h e f i n a l r e p o r t .
W e do&t h a v e t h e t i m e t o a n a l y z e i t h e r e . S e v e r a l Kodak f i l m
t y p e s , s p e c i f i c a l l y t h e most p o p u l a r a n d commonly e n c o u n t e r e d
f i l m s a p p e a r e d d e g r a d e d i n moderate p e r c e n t a g e s i n most
c o l l e c t i o n s d u r i n g t h e 1930s. T h e s e i n c l u d e d S u p e r - s e n s i t i v e Pan
a n d P o r t r a i t P a n f i l m s . A v e r y h i g h p e r c e n t a g e of D u p o n t
D e f e n d e r f i l m d a t e d a f t e r 1 9 4 6 , p a r t i c u l a r l y A r r o w P a n a n d High
Speed P a n f i l m s were f o u n d degraded i n a lmost e v e r y c o l l e c t i o n
s u r v e y e d t h r o u g h o u t t h e c o u n t r y . A g f a / A n s c o f i l m t y p e s a p p e a r e d
degraded i n moderate p e r c e n t a g e s t h r o u g h o u t t h e c h r o n o l o g y i n
p e r c e n t a g e s s i m i l a r t o Kodak p r o d u c t s .
T a b l e 3 t o t a l s t h e number o f f i l m t y p e s ( n o t c h e s ) f o r e a c h
m a n u f a c t u r e r a n d t h e number of t h o s e f i l m t y p e s w h i c h h a v e
d e g r a d e d samples. A l l m a n u f a c t u r e r s ' n e g a t i v e s show a h i g h
p e r c e n t a g e o f f i l m t y p e s w h i c h h a v e d e g r a d e d , t h a t is , most
c e l l u l o s e acetate-based s h e e t f i l m c a n be a f f e c t e d i n t h e same
way. T a b l e 2 shows t h e t o t a l number of n e g a t i v e s sampled a n d
l i s t e d b y m a n u f a c t u r e r . T h i s i n d i c a t e s t h e p e r c e n t a g e of samples
f r o m e a c h m a n u f a c t u r e r t h a t were degraded. A g a i n r w i t h t h e
29
e x c e p t i o n of D u p o n t D e f e n d e r ( p o s t 1945) f i l m , p e r c e n t a g e s f o r
e a c h o f t h e m a n u f a c t u r e r s were r e l a t i v e l y c lose , v a r y i n g f r o m 19-
38% of t h e t o t a l sampled.
I t s h o u l d be n o t e d t h a t t h e p e r c e n t a g e s c i t e d i n t h i s
c o m p i l a t i o n a r e u s e f u l o n l y i n r e l a t i o n t o e a c h o t h e r i n t h e
s p e c i f i c c o n t e x t of t h i s p r o j e c t . T h i s is d u e t o t h e s a m p l i n g
m e t h o d w h i c h w a s h e a v i l y w e i g h t e d t o w a r d s u s p e c t c o l l e c t i o n s a n d
a r eas w i t h i n c o l l e c t i o n s . T h e s e f i g u r e s a r e n o t t o be
e x t r a p o l a t e d t o c o l l e c t i o n s o f ma te r i a l s n o t sampled. F o r
e x a m p l e , most c o l l e c t i o n s w i l l c o n t a i n f a r less t h a n t h e t o t a l
30.9% d e g r a d e d samples f o r t h i s s u r v e y . A v e r y l a r g e c o l l e c t i o n
may c o n t a i n o n l y a s m a l l p e r c e n t a g e o f d e g r a d e d n e g a t i v e s . The
U n i v e r s i t y o f L o u i s v i l l e ' s C a u f i e l d a n d Shook C o l l e c t i o n , f o r
i n s t a n c e , c o n t a i n s r o u g h l y 5000 d e g r a d e d n e g a t i v e s o u t o f a t o t a l
o f a p p r o x i m a t e l y 160,000 n e g a t i v e s , o r 3.1% P e r c e n t a g e s c a n
a l s o be s o m e w h a t d e c e p t i v e i n i n s t a n c e s w h e r e f e w samples were
r e g i s t e r e d , s u c h a s f o r H a m m e r f i l m .
A u s e f u l s u m m a t i o n o f t h e d a t a is s e e n i n a c h r o n o l o g i c a l
o v e r v i e w f o r e a c h m a n u f a c t u r e r o f t h e t o t a l number o f n e g a t i v e s
s u r v e y e d a n d t h e number of d e g r a d e d samples.
F i g u r e 1 s h o w s a c o m p a r i s o n b e t w e e n m a n u f a c t u r e r s a n d t h e
p e r c e n t a g e of d e g r a d e d samples. I t i n d i c a t e s t h e a v e r a g e f o r a l l
samples, a s w e l l a s t h a t f o r i n d i v i d u a l m a n u f a c t u r e r s .
Regard less of d a t a s k e w s c a u s e d b y s a m p l i n g s i z e , g e n e r a l t r e n d s
r e m a i n c o n s i s t e n t . Kodak f i l m a c c o u n t s f o r a l l o f t h e d e g r a d e d
samples da ted b e f o r e 1936. A f t e r 1936, t h e t o t a l p e r c e n t a g e f o r
a l l n e g a t i v e s becomes a n a v e r a g e o f t h e t h r e e major m a n u f a c t u r e r s
30
Table 2 Film Types by Manufacturer
Eastman Kodak-total types 19 Types degraded 15
AgfdAnsco Types degraded
8 7
Defender Types degraded
10 9
Hammer Types degraded
1 1
Table 3 Samples Totaled by Manufacturer
Total number of samples Total number degraded'
Percentage 30.9%
3396 1051
Eastman Kodak total samples 2607 Total number degraded 70 1
Percentage 2 6.8%
Defender (pre-1945) total Total number degraded
Percentage 19%
109 20
Dupont Defender (post-1 945) total 206 Total number degraded 192
Percentage 9 3 O/o
AgfalAnsco total Total number degraded
Percentage 29%
46 1 133
Hammer total 13 Total number degraded 5
Percentage 38.4 Vo
*The term degraded here refers to negatives which exhibit definite signs of acetate deterioration, level 4 or greater. Negatives which were only slightly warped and with no other indications of degrada- tion, such as acetic odor, were not included in these totals.
31
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i n d i v i d u a l p e r c e n t a g e s . A f t e r 1940, t h e Kodak a v e r a g e f e l l
c o n s i s t e n t l y below t h e mean , w h i l e A g f a / A n s c o a n d D e f e n d e r f i l m s
s u f f e r from h i g h e r t h a n a v e r a g e p e r c e n t a g e s o f d e g r a d a t i o n .
I t is i n t e r e s t i n g t o n o t e t h a t pre-1930 samples o f Kodak
s a f e t y f i l m s s h o w n o s i g n s o f s e r i o u s d e g r a d a t i o n . T h i s is
d e s p i t e t h e f a c t t h a t t h e s e f i l m s a r e most d e f i n i t e l y o n
c e l l u l o s e d i a c e t a t e f i l m base . T h e e a r l y samples were p a r t of
c o l l e c t i o n s w h i c h c o n t a i n e d o t h e r l a t e r d e g r a d e d samples. L a t e r
degraded Kodak f i l m s , e s p e c i a l l y t h o s e d a t e d a f t e r 1940, w e r e
p r o b a b l y made w i t h o n e o f t h e m i x e d c e l l u l o s e es te rs . B o t h
Agfa /Ansco a n d D e f e n d e r / D u p o n t D e f e n d e r p r o d u c t s were o n
c e l l u l o s e d i a c e t a t e f i l m b a s e t h r o u g h o u t t h e p e r i o d . T h i s
i n d i c a t e s t h a t a l l c e l l u l o s e e s t e r s a r e s u s c e p t i b l e t o
d e g r a d a t i o n a n d n o t j u s t d i a c e t a t e as h a d b e e n a s s u m e d b y some
c u r a t o r s . C o n v e r s e l y , n e g a t i v e s s t i l l i n g o o d c o n d i t i o n i n c l u d e
d i ace t a t e , a s w e l l a s t h e m i x e d es ters .
A l t h o u g h some degraded D e f e n d e r f i l m s were d a t e d b e f o r e
1945, t h e r e w a s a c l e a r i n c r e a s e i n t h e p e r c e n t a g e s of d e g r a d e d
f i l m a f t e r 1945, t h e y e a r t h a t D u p o n t a s s u m e d c o n t r o l o f t h e
c o m p a n y . [ 4 0 ] F o r i n s t a n c e , n o t c h K D e f e n d e r f i l m (X-F
P a n c h r o m a t i c ) d a t e d 1934-41 was f o u n d degraded i n o n l y one o f t e n
c o l l e c t i o n s w h i c h c o n t a i n e d t h e m . La ter D u p o n t D e f e n d e r f i l m ,
from t h e 1 9 4 6 - 1 9 5 5 per iod were f o u n d degraded i n n e a r l y 100% of
t h e samples s u r v e y e d .
CONCLUSION
"The h i s t o r y o f a c e l l u l o s e d e r i v a t i v e can n e v e r be c o m p l e t e l y known, a n d so t h e e x a c t b e h a v i o u r of a g i v e n sample c a n n o t be p r e c i s e l y pred ic ted or e x p l a i n e d . " V i v i a n S t a n n e t t , C e l l u l o s e Acetate P l a s t i c s , 1951.
33
This statement best describes the difficulty in discussing
the problem of deteriorating safety-based photographic negatives.
A s described in the full report, the number of technical and storage
variables make exact explanations extremely difficult. Each
collection is different in terms of storage histories, present
storage conditions, enclosure materials, the presence of nitrate
film, and other specific factors.
Several generalities are obvious from an analysis of the
data and from obvservation, interviews, and literature search.
First, some individual collections contain a far greater number
of degraded samples than other collections and some institutions
contain more of these degraded collections. The following are
the major factors which relate directly to the condition of
negative collections:
1. temperature and humidity history; 2. storage of nitrate negatives with safety film; 3 . storage in acidic sleeving material; and 4 . the microenvironment of the negatives.
Temperature - and Humidity History
Given the well-documented susceptibility of cellulose
acetates to hydrolytic degradation, it is no surprise that the
temperature and, more importantly, the humidity history of a
collection plays a major role in the present state of
preservation of a negative collection. Many of the collections
faced with serious degradation were produced and/or stored in
geographic areas with a high average relative humidity or the
specific storage history of individual collections has included
some degree of temperature and humidity trauma at some point in
34
t h e i r l i f e t i m e before a r r i v i n g a t a n i n s t i t u t i o n .
C o l l e c t i o n s s to red i n g e o g r a p h i c a reas w i t h l o w r e l a t i v e
h u m i d i t y a n d i n f r e q u e n t d r a s t i c f l u c t u a t i o n s h a v e g e n e r a l l y f a r e d
much be t te r . T h e s e i n c l u d e c o l l e c t i o n s i n C a l i f o r n i a a n d
A r i z o n a . C e r t a i n f i l m t y p e s , m a i n l y Dupon t D e f e n d e r r degraded i n
t h e s e l o c a t i o n s a s w e l l , b u t most ace t a t e f i l m is s t i l l i n
r e l a t i v e l y g o o d c o n d i t i o n i n t h e s e c o l l e c t i o n s . On t h e o t h e r
h a n d , c o l l e c t i o n s a n d i n s t i t u t i o n s loca ted i n areas o f h i g h
a v e r a g e r e l a t i v e h u m i d i t y c o n t a i n f a r more d e g r a d e d n e g a t i v e s o f
a l l t y p e s a n d m a n u f a c t u r e r e s . T h e F l o r i d a S t a t e A r c h i v e s , t h e
U n i v e r s i t y o f L o u i s v i l l e , t h e H i s t o r i c N e w O r l e a n s C o l l e c t i o n ,
a n d s e v e r a l c o l l e c t i o n s i n W a s h i n g t o n , D.C. a re g o o d e x a m p l e s .
C o l l e c t i o n s s to red " p r o p e r l y " w i t h o u t e x t r e m e s i n
t e m p e r a t u r e o r h u m i d i t y a n d w i t h o u t s i g n i f i c a n t " t r a u m a " a l s o
seem t o c o n t a i n f a r f e w e r d e g r a d e d e x a m p l e s of a l l t y p e s a n d
m a n u f a c t u r e r s . Most n o t a b l y i n t h i s c a t e g o r y is t h e c o l l e c t i o n
a t t h e A m e r i c a n Museum o f N a t u r a l H i s t o r y . A l t h o u g h t h e
c o l l e c t i o n c o n t a i n s a l a r g e number a n d v a r i e t y of f i l m t y p e s of
s eve ra l s i z e s , t a k e n b y many p h o t o g r a p h e r s o n l o c a t i o n s
t h r o u g h o u t t h e world, t h e c o l l e c t i o n is i n v e r y g o o d s h a p e w i t h
o n l y o n e small p o c k e t o f degraded n e g a t i v e s . N e i t h e r temperature
o r h u m i d i t y h a s b e e n a c u r a t e l y c o n t r o l l e d a t t h e AMNH, b u t
c o n d i t i o n s h a v e been k e p t moderate and c o n s i s t e n t .
A major c h a n g e i n t h e average r e l a t i v e h u m d i t y w i t h f r e q u e n t
p e a k s over 80% a l s o seemed t o be a causa l f ac to r i n t h e r a p i d
i n c r e a s e i n t h e d e g r a d a t i o n of n e g a t i v e s a t t h e U n i v e r s i t y of
L o u i s v i l l e P h o t o g r a p h i c A r c h i v e s .
O t h e r c o l l e c t i o n s w h i c h c o n t a i n degraded n e g a t i v e s h a v e
35
histories which often include other forms of moisture trauma,
such as fire or flood. Observation of the various portions of
the Samuel Gottscho Collection (currently housed in three
separate locations, fully described in the Report) indicate that
early storage conditions, by the photographer or originating
agency, are more responsible for present degradation than more
recent institutional storage conditions. Degradation which may
have started years ago can dramatically increase in rate with
continued humidity trauma. It is believed that degradation can
be appreciably slowed by colder and dryer storage, but it is not
believed that the degradation can be arrested once it has
started.
Improper storage is not the only cause of serious
degradation, but proper temperature and humidity are extremely
critical for the long-term storage of all cellulose acetate
photographic negatives, pastr present, and future. The
recommended levels for both medium term and archival storage can
be found in American National Standards Institute specification