Article: THE ACETATE NEGATIVE SURVEY: FINAL REAuthor(s): David Horvath Topics in Photographic Preservation, Volume 2. Pages: 25-39 Compiler: Maria S. Holden © 1988, Photographic Materials Group of the American InstHistoric & Artistic Works. 1156 15th St. NW, Suite 320, Wa452-9545, www.aic-faic.org. Under a licensing agreement, icopyright to their work and extend publication rights to the AConservation. Topics in Photographic Preservation is published biannuallyMaterials Group (PMG) of the American Institute for ConseWorks (AIC). A membership benefit of the Photographic MPhotographic Preservation is primarily comprised of papersand is intended to inform and educate conservation-related d Papers presented in Topics in Photographic Preservation, Vformal process of peer review. Responsibility for the methodherein rests solely with the authors, whose articles should nostatements of the PMG or the AIC. The PMG is an approvednot necessarily represent the AIC policy or opinions.

PORT

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.

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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

PH1.43-1985. Archival storage requirements recommend 30%

relative humdity with little short-term recycling and a maximum

temperature of 21 degrees C (70F).

Storage of Nitrate Film - - Another factor which plays a major role in the process of

degradation is the storage of cellulose nitrate negatives in the

same or adjacent storage areas. These effects are well-described

by Carroll and Calhoun in their study “The Effect of Nitrogen

36

Oxide Gases on Processed Acetate Film". They concluded that the

combination of nitrogen oxides and high humidity are particularly

damaging, a fact that has particular relevance for the

collections surveyed.

Storage Enclosures

A third storage-related condition frequently encountered

with these collections was the presence of improper filing

enclosure materials. Kraft paper, glassine, and highly acidic

negative envelopes generally seem to accelerate the process of

deterioration. Many degraded negatives begin to show separation

of the base and emulsions along the seam of these envelopes.

Negatives stored in glassines often show signs of degradation

before similar unsleeved negatives or those in paper sleeves.

The Microenvironment - The physical microenvironment of each negative may also be

important to the rate of degradation. More evidence needs to be

collected concerning the effects of sleeving a collection of

previously unsleeved negatives. Normally the storage of

degrading negatives unsleeved in bundles or packs will increase

the autocatalytic reactions in the container, and effect more of

the surrounding negatives. However, sleeving may appear to

increase the rate of the degradation of particular negatives.

This seems to be evident in a number of cases as related by

collection curators, where previously unsleeved negatives, boxed

or bundled in stacks, were sleeved, and the degradation seemed to

speed up. This may be due, in part, to the fact that "looser"

sleeving provides more surface exposure for interaction between

37

the negative and moisture, oxidizing pollutants, and, perhaps

most importantly, with gaseous acetic acid produced by cellulose

acetate degradation.

Currently there is not enough data to predict whether

sleeving will accelerate or decelerate the rate of deterioration

of negatives that hawe already begun the degradation process.

Further observation and investigations are required to help make

the decision as to the appropriate action.

These storage and environmental factors are important in

that they offer immediate and observable connections which help

to explain the degradation of cellulose acetate negatives. No

factor can be identified as a single cause of the problem in all

cases. More likely it is a combination of these factors which

contribute to the autocatalytic process described in Section 3 .

But questions must still be asked, such as why do some

negatives within a collection which have always been stored

together degrade first? will collections and institutions which

now contain a few of these degraded products begin to see similar

"pockets" of deterioration in coming years?

The first question can be answered simply by admitting that

certain negatives seem to be "predisposed" to more accelerated

degradation and susceptibility to environmental factors. This

conclusion is supported by the observation that negatives from

some manufacturers made during specific time periods have a very

high incidence of degradation. This is most eyident in the

Defender f i l m manufactured between 1947-1955, and, to a lesser

38

d e g r e e , some Kodak f i l m i n t h e 1930s.

I t is b e l i e v e d t h a t " p o c k e t s " o f d e g r a d a t i o n s p r e a d b e c a u s e

o f t h e c a t a l c y t i c e f f e c t of t h e d e g r a d a t i o n b y - p r o d u c t s wh ich

i n f e s t more s t ab le mater ia ls . It would n o t b e i n a c c u r a t e t o

r e l a t e t h i s t o t h e "bad a p p l e " phenomenon.

A more exact a n s w e r t o t h i s q u e s t i o n would b e s p e c u l a t i v e

w i t h o u t c o n s i d e r a b l e a n a l y t i c a l t e s t i n g o f h i s t o r i c a l n e g a t i v e s .

T h i s s p e c u l a t i o n is made more d i f f i c u l t b e c a u s e o f t h e l a r g e

number of v a r i a b l e s i n v o l v e d .

The s e c o n d q u e s t i o n c a n be a n s w e r e d w i t h a l i t t l e more

c e r t a i n t y . G i v e n t h e e v i d e n c e f r o m t h i s p r o j e c t , e x a m p l e s

o f d e g r a d e d s a f e t y f i l m are w i d e s p r e a d , w i t h m o s t i n s t i t u t i o n s

s u r v e y e d c o n t a i n i n g a v a r i e t y of d e g r a d e d e x a m p l e s f rom a l l

m a n u f a c t u r e r s . I t is c o n c l u d e d t h a t e v e r y i n s t i t u t i o n wh ich

c o n t a i n s a s u b s t a n t i a l q u a n t i t y o f s a f e t y f i l m d a t i n g from 1925-

1955 w i l l f i n d p r o b l e m s w i t h d e g r a d e d f i l m b a s e somewhere i n

t h e i r c o l l e c t i o n s o o n e r o r l a t e r . The e x t e n t a n d b r e a d t h of t h e

p r o b l e m w i l l v a r y , j u s t as it h a s w i t h t h i s s u r v e y , from

i n s t i t u t i o n t o i n s t i t u t i o n d e p e n d i n g o n s to rage h i s t o r y a n d t h e

o t h e r fac tors as described i n t h i s r epor t .

( A complete c o p y 02 t h e R e p o r t c a n be o b t a i n e d f o r $10 b y w r i t i n g

t o 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 , E k s t r o m

L i b r a r y , L o u i s v i l l e , KY 4 0 2 9 2 )

39