preservation management of photographic collections 21 … · handling photographic media 4 cotton,...

D A T E

1

Preservation Management of Photographic Collections

21 September 2011

Preservation Management 2

Traditional photographs /Digital photographs

Identification

Storage enclosures

Storage environments

Must Have Resources 3

Handling Photographic Media 4

Cotton, latex or nitrile gloves must be worn when handling all photographic materials

Negatives should be handled in a well-ventilated room

Before removing a negative from an envelope transfer all catalogue to the new negative

Only pencil should be used to write on the new envelope

The emulsion side of the negative should be placed away from the envelope seam

Never re-use an envelope that has been used to store cellulose nitrate or cellulose acetates

6B pencil or permanent pigma pen

Gloves Do Matter 5

Cased Photographs 6

Daguerreotypes 7

Introduced in France 1839

Early 1840s – early 1860s

Whites/highlights are silver mercury

dark areas pure silver metal – highly polished

Silver mercury amalgam

Copper Plate

Silver Plated Surface

Daguerreotype 8

Malcolm Daniels, Curator of the Dept of Photographs at the Metropolitan Museum of Art (4.39)

C:\Documents and Settings\Rosaleen\My Documents\My Videos\RealPlayer Downloads\Daguerreotypes at the Met. - YouTube.flv

Ambrotype 9

1855 – 1865 – most popular in late 1850s

Wet collodion negative with dark background forms a positive image

Dark layer – applied or separate

Glass support

Collodion/silver salts

Varnish

Ambrotype Identification 10

No mirror-like surface

May have rose coloured glass

3D quality as the black/dark background is physically separated from the image highlights

Tintypes 11

1856 patented in US – into 20thc

Ferrotype or Melainotype

Inexpensive – street photographers

Japan BlackVarnish Sheet Iron

Japan BlackVarnish Collodion/ silver salts

Varnish Copal

Tintype Identification 12

Unmounted – magnet

Cased – magnet on glass

Can be coloured with dry pigments

Later tintypes inserted in paper cards – often card was embossed

Bends easily – fractures layer structure allowing rust to form

Cased Photo Storage 13

Mylar lift

Prints – paper base 14

Print Identification

30x magnification

Print Identification 16

One layer print

No Baryta layer – (barium sulfate)

One Layer

17 No binder No baryta layer

Paper fibers clearly visible

Matt surface

Print Identification – 1 Layer 18

Fibres visible no baryta layer

Platinum/Platinotype – 1 Layer 19

1873-76 US patents

Popular from 1890s –

Full grey scale range –– very stable

Matte surface

Platinum on/in paper surface

Platinum Identification 20

Range of greys – no fading

Catalyzes paper deterioration

Fibres clearly visible

Cyanotype 21

Blue

Print Identification 22

Two layer print – albumen print

Two Layer 23

Albumen (POP) 24

1850 Blanquart Evrard outlined process to French Academy of Sciences

1855 – 1895 ~ 85% of 19th century photos

Paper floated on egg white/ammonium or sodium chloride bath

To sensitize - paper then floated on a silver nitrate bath for 2 – 3 minutes

Rag paper – light weight

Albumen /photolytic silver

Albumen Identification 25

Paper fibres visible at 30X mag

Crack pattern

Albumen Identification 26

Most mounted on cards

Carte de visite - 2.5 x 4.25 “

Cabinet - 4.5 x 6.25”

Victoria - 3.25 x 5”

Promenade – 4 x 7”

Boudoir – 5.25 x 8.5”

Imperial – 6 7/8 x 9 7/8”

Panel – 8.25 x 4”

Print Identification 27

Three layer

Three Layer

28

Print Identification 29

Fibres not

clearly

visible

Baryta layer

30

Matte or Glossy Collodion POP 31

1890s – 1910s

Most frequently studio portraits – often oval

Baryta could be textured or pigmented

Sometimes called Aristotypes

Paper

Baryta

Collodion /photolytic silver

Silver Gelatin DOP 32

1880s –

Moved from silver chloride to silver bromide – baryta could be textured

Fibre and resin coated (RC) papers

Paper

Baryta (BaS04 + Gelatin)

Emulsion Silver Bromide

Gelatin Super coat

Mirroring 33

Photomechanical – NOT Photos 34

35

Postcard Photographs 36

37

Storage Enclosures: Paper 38

All materials should pass the Photographic Activity Test (PAT)

Buffered paper (pH 7 – 9.5) for all B/W photographic media.

Colour or processed diazo photographic materials may be stored in buffered envelopes that pass the PAT. The acceptable pH should not exceed 8.

Use side seam envelopes with emulsion side away from the seam

ISO 18902-2007

39

Molecular Sieves 40

Zeolites – aluminosilicates Porous compounds – trap molecules whose size is

compatible with their micropores

Acid Scavengers Acetic acid = Type 4A molecular sieve

Oxygen Scavengers

mixture of a metal powder (usually iron) and sodium chloride in bag Ageless Z

Exothermic

Storage Enclosures Paper – Advantages/Disadvantages

41

Opaque – protect from light but also means more handling as the photo has to be removed to be seen

Porous – off-gassing chemicals can escape – rh

Cost – generally less expensive than plastics Identification – write with pencil on paper

Microchamber paper – new – scavengers

charcoal, zeolites

ISO 18902

Storage Enclosures Plastic

42

All materials must pass the PAT

Safe plastics include polypropylene, polystyrene, HD polyethylene, polyester

Non-porous - can lead to ferrotyping

Avoid plastics with PVC, plasticizers and other additives

Beilstein Test – CCI Note 17/1

Trade names include Print File, Clear Vue

Magnetic albums 43

Kiss of Death!

ISO 18920 44

Photographic Negatives

Why Identify Negatives 46

Separate and rehouse negatives based on film base type

Identify stages of deterioration in order that priority rankings can be made for reformatting and/or cold storage

Metadata information for electronic copies

Health and Safety 47

Deteriorating cellulose nitrate and acetates have been known to cause health problems

Symptoms have included: Eye irritation, rashes, nausea, respiratory problems and others

Hollinshead, Patricia W., Ert, Mark D., Holland, Steven C., and Kathy Velo. 1987.

"Deteriorating Negatives: A Health Hazard in Collection Management," . Tucson, AZ: Arizona State Museum

http://www.statemuseum.arizona.edu/coll/healthhazard/phot_neg_hazard.pdf

Photographic Negatives 48

4 Major categories

Glass plate

Cellulose nitrate

Cellulose acetate(s)

Polyester

Glass Plate Negatives 49

Wet plate – collodion 1848-late 1870s

Hand coated just prior to use

Up to 18 x 22” = Mammoth Plates

Glass Plate Negatives 50

Dry plate – gelatin 1870s-1910s

Commercially produced

Dry Plate – Emulsion Lifting 51

Broken Glass Plates 52

Broken Glass Plate Housing From Carolyn Long Recommendations for Storage and Exhibition of

Photographic Materials Smithsonian 1989

Glass Plate Housing 54

Photographic Negatives 55

Cellulose nitrates (1889 – 1950s)

Cellulose acetate(s) (1925 – present)

Polyester (1960 – present)

Cellulose Nitrate Timeline 56

Film Type Last Year

Roll Film 1938

Portrait/Commercial Film 1939

Film Packs 1949

Pro 35mm Film 1951

*film may have been stockpiled so you will see nitrates after last year dates

*16mm was never manufactured in cellulose nitrate

Cellulose Nitrate Deterioration 57

Deterioration, once started, can only be stopped by putting negatives in cold storage.

Deterioration is accelerated by poor storage conditions;

High RH, high temperature, poor air circulation

Deterioration nitrate negatives can affect adjacent materials

Flammable

Cellulose Nitrate – Stage 1 58

Amber

discolouration

with fading of

filamentary

silver image

Cellulose Nitrate - Stage 2 59

Emulsion is

adhesive-like

Cellulose Nitrate – Stage 3 60

Gas bubbles, odour, and embrittlement

Cellulose Nitrate – Stage 4 61

Film softens,

viscous substance

is formed

Cellulose Nitrate – Stage 5 62

Brownish, acid powder

Cellulose Nitrate Storage Plan 63

Separate and store away from other photographic materials

Storage area should be exhausted to the outside

Do not store in plastic enclosures – use buffered acid-free paper envelopes that have passed the PAT

Deteriorating nitrates should be scanned

Cold storage

NFPA 40 64

2007 National Fire Protection Association

Standard for the Storage and Handling of Cellulose Nitrate Film

www.nfpa.org

Cellulose Acetate(s) 65

First used for 16mm amateur film

“Safety”

Ester family : Cellulose acetate propionate

Cellulose acetate butyrate

Cellulose triacetate

Cellulose Acetate Timeline 66

1923 Kodak cellulose diacetate 16mm film

1925 Kodak cellulose diacetate sheet film to 1940

1927 Kodak intro cellulose acetate propionate

1930s Other manufactures produce cellulose acetates

1936 Kodak intro cellulose acetate butyrate

1948 Kodak intro cellulose triacetate

Cellulose Acetate - Stage 1 67

Flat with no visible

deterioration

Cellulose Acetate - Stage 2 68

Slight or

moderate

edge curl

Cellulose Acetate - Stage 3 69

Characteristic vinegar smell becomes noticeable

Cellulose Acetate – Stage 4 70

Warpage

and

Shrinkage

3mm

Cellulose Acetate – Stage 5 71

Plasticizer migration

Cellulose Acetate – Stage 6 72

Emulsion separation

Anti-halation Layer 73

Cellulose Acetate Cross-Section 74

____________ Gelatin supercoat

______________ Top gelatin emulsion

______________ Lower gelatin emulsion

______________ Subbing layer – CN and CA

xxxxxxxxxxxx Cellulose acetate(s)

______________ Subbing layer

______________ Anti-halation /Anti-curl

Polyester 75

Polyethylene terepthalate

Introduced in the 1950s

Dupont introduced and called it Cronar – Kodak then bought Cronar and renamed it Estar

LE of 500 years (Acetates 100 years)

Negative Identification Methods 76

Non-destructive

Destructive

Is Edge Printing Visible? 77

Polarizer Test 78

Identifiable Notch Code? 79

Identified from Accession Records? 81

1889 Eastman Kodak – first cellulose nitrate roll film

1913 Nitrate sheet film produced

1923 First cellulose acetate film produced (16mm motion picture film only)

1939 Portrait and commercial sheet film – Kodak, last date of manufacture

1947 Cellulose triacetate first produced

1950 Nitrate motion picture film discontinued by Kodak

in U.S.

1955 First polyester film manufactured by DuPont

2000 Cellulose triacetate and polyester still in use

Characteristic Stages of Deterioration 82

Cellulose nitrate - 5 stages

Cellulose acetate – 6 stages

Destructive Testing 83

Diphenylamine Test (DPA)

Burn Test

Trichloroethylene Test

Diphenylamine Test 84

The DPA tests for presence of cellulose nitrate

Positive test is the formation of a dark blue/purple stain in the reagent

CCI Note 17/1

Advantages: very small sample size

Disadvantages: can get false positives

Cellulose Acetate Cross-Section 85

____________ Gelatin supercoat

______________ Top gelatin emulsion

______________ Lower gelatin emulsion

______________ Subbing layer – CN and CA

xxxxxxxxxxxx Cellulose acetate(s)

______________ Subbing layer

______________ Anti-halation /Anti-curl

Trichloroethylene 86

Allows for identification based on the differential densities of the plastic film bases

Least reliable as the densities of the plastics change with deterioration

Trichloroethylene is a carcinogen

CN sinks CA top Polyester middle

Cold Storage for Photographic Collections 87

Cellulose nitrate

Cellulose acetate

Color photographic media

Three Types of Cold Storage 88

1. Custom engineered walk-in cold vault RH control in vault

Difficult to maintain relative humidity

Expensive to operate

2. Walk –In Freezer with Gasketted Cabinets 89

RH control in gasketted cabinets

3. Microclimate Packing with Convention Freezer

90

RH control in storage package

Inexpensive

Based on Smithsonian Institute Research

Cold Storage Environment 91

Temperature:

below 0ºC (32 ºF)

generally around -18 ºC (0 ºF)

Relative Humidity:

30-50%

Why Should You Consider Cold Storage? 92

Increases life expectancy of collection

Rate of chemical deterioration decreases dramatically

Buys time to implement reformatting program

Allows for effective combination of reformatting (digitizing or traditional copy negs and long-term storage)

IPI Preservation Calculator 93

IPI Preservation Calculator 94

How to Proceed 95

1. Collection Survey

What type of negatives do you have?

What stage of deterioration?

This allows priorities to be drawn

What is the size of your collection?

96

Cellulose Acetate Autocatalytic Point

97

A-D Strips 98

99

Band 1-2 (blue green) – deteriorating but not a serious concern yet

Band 2 or higher (olive) – 0.5 autocatalytic point

Band 3 (yellow) – vinegar smell

Factors to Consider 100

1. Out of cold storage time

2. Access Copy negatives (polyester film base)

Digitizing

2. Walk –In Freezer With Gasketted Cabinets 101

Wilhelm Imaging – Iowa

City of Vancouver Archives

Cabinet 102

~50,000 5 x 7” cellulose acetate negatives

Pre-conditioned mat board

Retrieval 103

Igloo Cooler Temp – 3 remotes

3. Microclimate Packing with Convention Freezer

104

RH control in storage package

Inexpensive

Based on Smithsonian Institute Research

For small collections – or use an interim measure

Numbers 105

5x7” negatives

25 negs per package

6 packages per box

150 negs per box

18+ boxes per 20 cu ft freezer

2700+ negs per freezer

(Numbers courtesy of Betty Walsh, RBCM)

Packing System – Metaledge Inc 106

Colour slides

20 slides per page (PP)

25 – 30 pages per box

500 – 600 slides per box

20 box/freezer = 10 – 12K

www.metaledgeinc.com

Warm-up Times 107

Depends on thermal mass of package

e.g.. 2.5 cm thick = approx. 2 hours = one negative package not one box

Condensation on outer bag is normal

Always better to err on the long side of a warm-up time

US National Parks Service http://www.nps.gov/museum/coldstorage/html/intro1_1.html

108

Preservation Supply Companies 109

Carr McLean www.carrmclean.ca

University Products www.universityproducts.com

Hollinger Metal Edge www.hollingermetaledge.com