Levanger Report by Preus museum

NORSK MUSEUM FOR FOTOGRAFI - PREUS FOTOMUSEUM Pb. 254, N-3192 Horten Tlf: +47 33031637 Fax: +47 33031640 jens.gold@foto.museum.no

Horten, 29.03.2004

Survey / Condition Report on the photographic color materials of the RenbjĂ¸r collection in the Levanger museum

Jens Gold - Photograph Conservator

Introduction In 2002 the Levanger Museum acquired the complete private chemistry research lab for black and white and color photography of Harald Renbjør (1889 – 1956), a very ambitious chemist and former student of Professor Josef Maria Eder at the Graphischen Lehr- und Versuchsanstalt Wien. The complete collection of objects is unique because they represent about 120 years of photo history and work on all kinds of photographic materials. This lab, which was a part of the commercial Renbjør photo lab and the first color photo lab in Norway, had been left untouched since the death of Harald Renbjør in 1956. During the research documentation work in the old Renbjør chemistry lab in 2002, the staff of the Levanger Museum discovered a great collection of about 13500 pieces consisting of various photographic materials, obviously a part of Renbjør´s research work.1 Approximately 3000 of these objects are color materials, and among them some of the earliest examples of color photography in Norway. For the Levanger Museum it was clear that these materials are a very important part of the history of Norwegian (color) photography and also of the history of Levanger. Subsequently Levanger Museum contacted the new conservation department in the Norsk museum for fotografi Preus fotomuseum in order to get a conservation survey over the most sensitive part of the Renbjør collection, - the photographic color materials. A survey was executed in December 2003 resulting in this report informing on the different types of color material in the Renbjør collection, their condition, reasons for deterioration and the need for conservation/ preservation work.

Table of Contents The different types of color materials in the RenbjĂ¸r collection

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Assembly process / Pinatypi

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Screen processes

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Lenticular screen process

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Chromogenic materials [slide and print materials] Technicolor process

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Dye destruction process / Pantachrome Total amount of color materials

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The condition of the photographic materials [the various types of deterioration and damages]

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What can be done? Stabilization / Preservation

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What can be done? Conservation / Restoration

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Appendix

Illustrations/ Reproductions Bibliography Endnotes

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The different types of color materials in the RenbjĂ¸r collection Assembly process / Pinatypi The RenbjĂ¸r collection contains a rather uncommon early subtractive color process, the Pinatypi process, which was invented by the Frenchman Leon Didier in 1903. Hoechst AG in Germany worked out the details of the process and produced equipment and materials. Since the process was very timeconsuming and complicated, the Pinatypi process was not often used. To make a Pinatypi it is necessary to produce three color separation negatives (Fig. 1) from the object recorded: a red, green and blue record on a panchromatic black and Fig. 2 white emulsion. From the negatives the photographer makes three separation black and white positives (Fig. 2).2 After which a gelatin emulsion of transfer material, treated/ sensitized with a dichromate, is exposed under the separation positives. The exposed part of the gelatin hardens according to the density of the negative. After processing (washing), the transfer material is dyed with a dye of the complementary color of the used filter-color in the camera (Fig. 3). The unhardened part of the gelatin is able to absorb the dye. This transfer sheet is brought in contact, face to face, with a moist receiving gelatin layer on the final printing paper. The dye in the dichromate paper transfers now to the gelatin on final print support (German: Absaugprozess). This process is done with all transfer sheets (cyan, magenta and yellow) under control of register marks on to the final support (Fig. 4 & 5).3 Almost all materials for the different process steps can be found in the RenbjĂ¸r collection in good and very good condition and different quality. Fig. 1

Process - Pinatypi plates and transfer material - Pinatypi prints - separation negatives

Sizes - 9 x 24 cm (glass plate, one sheet, three color separation negatives) - 9 x 8 cm (glass plate, three color separations) - 8 x 12 (glass plate negatives, custom cut) - 9 x 12 (glass plate negatives) - Pinatypi prints ca.: 8 x 8 cm, - Pinatypi prints 9 x 12 cm - 9 x 12 (glass plate, three color separation negatives)

Quantity together 225

Fig. 3

Fig. 4 & 5 5

Screen processes From the end of the 19th century to the beginning of the 1930s more than hundred color screen processes were invented. Among the most successful were the Autochrome (Fig. 6 & 7), Agfacolor Farbenplatte (Fig. 8), Kornrasterfilm/ Agfacolor – Ultra, (Fig. 9), Dufaycolor (Fig. 10) and Finlaycolor process (Fig. 11) which all are represented in the Renbjør collection. All these screen processes work after the principles of Ducos du Hauron who patented his ideas concerning color reproduction in 1868. After the discovery of color sensitive black and white emulsions by H. W. Vogel it ~ x 40 was possible to make practical use of Haurons ideas. In 1907 the Lumière brothers Fig. 7 launched the Autochrome process, the first industrial/ commercially used color process. The process was used and very popular from 1907 until the 1930’s. During this time approximately 20 000 000 Autochrome plates were exposed and developed. The Autochrome process was three years earlier patented in London and works like all screen Fig. 6 processes after the principals of additive color reproduction.4 On this point I like to use the example of the Autochrome to show how a screen process works. The Autochrome process is based on the use of starch grains of an almost uniform size, dyed in the necessary colors red, green and blue-violet (Fig. in Fig. 7), mixed and sifted on to glass coated with tacky varnish. After this, the grains are rolled under high pressure and interspaces between the grains are filled with black carbon pigment. The screen plate is then coated with a water resistant varnish and after that with a panchromatic emulsion, thus sensitive to the whole spectrum of visible light. For camera exposure the Autochrome plate is placed with the glass side to the lens so that the light can pass through the colored starch grains and expose the black and white emulsion. After exposure follows a black & white reversal processing so that a positive color image can be seen through the colored starch screen. The only significant difference to other screen processes is the form of the screen that is used to filter the light and the application of it. For example, Agfa used a screen consisting of colored lacquer particles (Fig. in Fig. 8) (Agfacolor6

Platte) or colored resin particles (Agfacolor-Ultrafilm). The Dufay- and Finlaycolor (Fig. 10, 11) material (and many more) used, instead of a random particle screen, a specific colored pattern (Linienraster in Fig. 10 & 11) for the screen.5 Process Autochrome

Sizes - 4,4 x 4,4 cm (custom cut) - 4,5 x 6 cm (custom cut from 9 x 12 plates) - 6 x 9 cm (custom cut from 9 x 12 plates) - 8,2 x 12 cm (custom cut from 9 x 12 plates) - 9 x12 cm - 5” x 7”

Quantity 42

Agfa fargeraster / Agfacolor Farbenplatte

- 6 x 8 cm (glass plate) - 9 x 12 (glass plate) - 5” x 7” (sheet film) - 6 x 8 cm (120 - film)

Agfa Kornraster /Agfacolor - Ultrafilm Dufaycolor

135 - film 135 - film (most part) 120-film (1 roll)

Finlaycolor

135 - film

~ x 40

Fig. 8

Fig. 9

~ x 50

~ x 100 Fig. 10

Fig. 11

Lenticular screen process An image from a camera lens can be re-imaged in form of a series of minute points or lines (Agfa and Kodak Linsenrasterfilm) with the help of a lenticular screen. A lenticular screen is a screen which is made of a transparent material (gelatin or plastic), embossed with a pattern of microscopic small lens segments (Fig. in Fig. 12). In the case of the AgfaLinsenraster material the lens segments are cylindrical, forming a series of parallel ridges. When a Linsenrasterfilm is in a camera positioned ~ x 50 with the lenticular surface to the camera lens, each lenticular segment sees a different point of the image from a unique angle and re-images it as a distinct element in the emulsion. A filter divided into three primary color bands (red, green and blue) is used at the lens. Light from each subject point strikes lens and filter. In each band only the light color corresponding to the filter color is transmitted thus performing the three color analysis for the color reproduction. The lenticular screen forms a distinct Fig. 12 record of the amount of light from each filter band on each subject point (Fig. 13). After exposure the emulsion is reversal processed, the densities of each lenticular segment corresponds to the variations in the exposing light. When the film is projected through a matching lens-filter system, the light of all the lenticular elements is colored and the image can be seen as a full color image. With this system it is not necessary to apply the screen directly to the emulsion or to register a screen with the emulsion after processing, it is much simpler. The most patents in the 1920s were on the lenticular screen process. In 1928 Kodak introduced the first color motion picture material (Kodak color) with the lenticular screen system. Agfa followed in 1931 with a material of higher resolution (Agfacolor).

Process Agfa-Linsenrasterfilm

Sizes Quantity 135 - film 3 16 mm 3 pieces = 237 cm It was possible to make positive color copies from the lenticular material, for example with the Pantachrome material.

Fig. 13

Chromogenic material Rudolf Fischer, who patented the use of color couplers in 1912/1914, coined the term chromogenic which can be translated as â&#x20AC;?give birth to colorâ&#x20AC;?. In chromogenic development a dye image is produced in the emulsion as an exposed silver image (the latent image) is developed. The dyes are formed by color couplers, which are colorless until they react with the developer oxidation products of their associated silver halide crystals to a visible dye. After the dyes are developed the silver image in the emulsion is bleached away so that only the dyes and unused color couplers remain. Almost all photographic color materials today use chromogenic development to produce cyan, magenta and yellow dyes in a multilayer emulsion (Fig. 14 emulsion on a chromogenic paper print). The stability of todayâ&#x20AC;&#x2122;s material has gained a great deal Fig. 14 compared to the earlier examples represented here in this collection. The major problems in the past were the instability of the dyes and that dyes and the unused color couplers could start to wander and deteriorate (Fig. 15) in the emulsion. This would depend also on the storage and display conditions, but if occurring, some dyes may fade or new dyes may develop (with the help of unused color couplers remaining in the emulsion). The typical color shift and fading of earlier slide, motion picture and print material can be Fig. 15 observed (Fig. 15, 16, 17).6 The only exception is the Kodachrome material where even 10

early examples often are in a superb condition. In the case of Kodachrome, the color couplers are in the color developer instead of in the emulsion. The advantage of this is that after processing, only the color image (the dye image) remains in the gelatin emulsion.7

Process Agfacolor positive color Agfacolor positive color Agfacolor positive color CT-18 Agfacolor positive color L UT 18 Agfacolor positive color L CT Agfacolor positiv color L UT Agfa negative color Agfa negative color Agfa color prints Agfa movie (single pieces): Ansco positive color Ansco positive color Ektachrome positive color Gevaert positive color Gevaert positive color Ilford positive color Kodachrome, positive color

Sizes 135 - film 9 x 15 135 - film

Quantity 1153 2 71

135 - film

135 - film 120 - film ca.: 10 x 10 cm , 7 x 10 cm, 10 x 10 cm, 9 x 12 cm, 12 x 16 cm 135 - film

115 128 69

135 - film 120 - film 135 - film 135 - film 120 - film 135 - film 135 - film

639 83 34 110 12 19 63

Fig. 16

Fig. 17

Technicolor process After a series of different approaches came the Technicolor Motion Picture Corporation, in 1932, to the three color Technicolor system. To produce a positive Technicolor image several steps were necessary. At first three black and white emulsions on three film supports were exposed in a complicated Technicolor three-strip beam splitter camera to get three color separation negatives. These color separation negatives were printed on three color separation matrice films, films which produce a gelatin relief that can be dyed with the necessary cyan, magenta and yellow dyes. The dyes from the matrice (transfer) material can then be transferred (Fig. 18) to the final support which carries also a black and white image from the green separation negative of the print and the sound strip of the movie.8 Process Technicolor, positive color

Sizes 135 - film

Quantity 3 pieces

Fig. 18

Dye destruction process / Pantachrome

Fig. 19

Fig. 20

In 1938 Agfa demonstrated for the first time the Pantachrome process (also called Tripofilm III fĂźr Silberbleichverfahren) (Fig. 19 Pantachrome in the RenbjĂ¸r collection) which was developed to make multiple color copies of the Agfa Linsenraster film. The Pantachrome material is a direct positive color material where the dyes are partly already in the emulsion (magenta and yellow on the front of the film support) and partly processed in the emulsion (cyan, on the back side of the film support) (Fig. 20, 21). The unnecessary magenta and yellow as well the associated black and white images are bleached away during processing. The necessary cyan part of the image is produced by toning the associated black and white image blue/green.9

Process Pantachrome, positive color

Sizes 135 - film

Quantity 2 Fig. 21

Total amount of color material Process Other techniques/ experimental (not identified)

Quantity 3

Total (all techniques, Fig. 22)

2939

Fig. 22

The condition of the photographic materials [the various types of deterioration and damages] Every thing has its time, also the most valuable objects in public and private collections. The reason for this is aging or in conservation term deterioration, which is part of the history of every (museum) object. In this case we have, despite the various signs of deterioration (Fig. 23, 24), a collection of photographic objects in relative good condition in relation to its age and previous storage conditions.

Fig. 23, 24 15

damage or deterioration type delaminating of image layers

condition information There are several factors that can contribute to a delaminating problem on a single or multilayer photographic material. The main reason is the use of materials with different rations of dimensional change/ different physical properties in the photography (gelatin, shellac, collodion, glass â&#x20AC;Ś) together with difficult processing and storage conditions such as swelling and drying of the emulsion during processing, bad processing, aggressive changes in temperature and relative humidity under storage, etc. In the RenbjĂ¸r collection there are glass plate negative material, Autochrome plates, Agfacolor plates and color filters that suffers from the whole range of such factors. Especially the color screen material which exhibit, on almost all plates, a tendency for delaminating in all stages (Fig. 24, 25, 26). Most of the glass plate separation negatives, Pinatypi transfer plates and films reveal generally just minor delaminating on the edges (Fig. 27, 28).

Fig. 25, 26

Fig. 27, 28

damage or deterioration type cracked glass supports silver mirroring

condition information Only a very few plates were observed with a cracked glass support (Fig. 1). Silver mirroring can be observed on the most of the black and white separation negatives (Fig. 29), Autochromes (Fig. 30, 31), and all other processes with silver emulsions. In some cases the Ag-mirror is visible all over the emulsion surface.

Fig. 30, 31

Fig. 29 17

damage or deterioration type mould and insect damages finger prints

condition information Mould is a general problem in collections containing organic materials. There is no way to get rid of mould but the improvement of storage conditions will prevent further growth. The condition for a mould attack must have been good on a certain point because the gelatin emulsions on almost all types of processes show minor but typical signs of mould damage (Fig. 32, 33). Mould growth is promoted above 60 % relative humidity (RH). Fingerprints are one of the most common problems in a photograph collection, so also here. In most cases they were caused by the photographer self. In the RenbjĂ¸r collection several very obvious damages are caused by fingerprints, they are especially visible on silver gelatin emulsions but also on color material like the Pinatypi transfer plates and films (Fig. 34).

Fig. 34

Fig. 32, 33 18

damage or deterioration type brown spots in Autochromes

green spots and lines in Autochromes

black spots in Autochromes

Fig. 35

condition information In some cases brown/yellow spots (Fig. 35) are seen on Autochromes in the RenbjĂ¸r collection. These spots are in the most cases products of local image silver deterioration. Autochrome plates have a very fine grain structure of the image silver, and it is known that emulsions with such grain size are very sensitive to oxidation. During the deterioration process the image silver can be converted to silver sulfide or colloidal silver which occurs in brown yellow color.10 Many of the examined Autochrome plates showed green spots and lines in various sizes in the filter layer of the plates. The causes of these spots are very small openings in the varnish and emulsion layer on top of the filter layer. Through this openings moisture can come to the filter dyes and attack especially the very water-sensitive green dye of the filter elements. The dissolved dye wanders through the filter layer and mixes with the other dyes and eventually settles in an area around the perforated layers (Fig. 36). After a longer exposure of the green discoloration to air, heat and moisture a change of color toward pink/ orange can appear (Fig. 24, 25, 26, 35, and 36).11 In the most cases black spots on Autochrome plates (Fig. 37) are caused by defects in the gelatin emulsion formed during manufacture. These spots can sometimes cover up a larger part of the emulsion surface or just a small area. Over time a small silver mirroring can develop on top of such black spots.12

Fig. 36

Fig. 37 19

damage or deterioration type curling film supports [deterioration of cellulose nitrate/acetate] water damages

condition information Some of the color slides and black and white negative material on film support exhibit a curling problem (Fig. 38, 39). There can be several reasons for that. The deterioration of cellulose nitrate or acetate starts with a deformation (shrinkage) of the plastic material. The change of dimension can cause such curling. A very hardened gelatin emulsion in addition to bad storage conditions (very low relative humidity and tight rolled storage) can also be a reason or contribute to the curling and deformation of the film support.13 Fortunately there are only a few objects in this collection which are damaged by water (Fig. 40, 41). Since the damages are very old and often also connected to mould damage and glass corrosion, there is not much hope of improvement except stabilization achieved through better storage and careful handling.

Fig. 40, 41 Fig. 38, 39 20

damage or deterioration type discoloration and color shift on chromogenic materials

condition information All chromogenic materials in the RenbjĂ¸r collection are in different states of fading (Fig. 42 - 47, fading c-prints, color slides) but many of these materials are in relatively good condition for their age. The dyes in chromogenic materials are in general known for there instability and fading behavior under long-term storage and display. Unfortunately the dyes in a chromogenic emulsion fade in different speeds so that a change in color balance is often soon visible in different color shifts. In addition to the fading of the dyes comes in some cases the deterioration of the unused color couplers which can cause a staining of the complete emulsion. The only chromogenic material in this collection that has a very good dark stability is the Kodachrome material. In the Kodachrome material there are no dye couplers incorporated in the emulsion layers, so a dye coupler staining will not happen in the future.14

Fig. 42 - 47

What can be done? Stabilization / Preservation Exercising care in handling and storage can extend the life of photographs. The American National Standards Institute, Inc. (ANSI) [Standard ANSI/NAPM IT 9.20-1996] and the International Organization for Standardization (ISO) [Standard ISO 18920:2000], offer recommendations for print enclosures, storage housing, storage rooms, print handling, and environmental conditions. Their suggestions on temperature, humidity, and light, etc. are worthy of review:15 1. The storage temperature should not be higher than 18 °C with a daily fluctuation not greater than +/- 2 °C. For color material a cold storage of about 5 – 10 °C with a daily fluctuation not greater than +/- 2 °C would be optimal for maximum life expectancy. 2. Emulsion layers become brittle below 30 % RH and mould growth is promoted above 60 % RH. The optimum range is: 30 – 40 % RH, a daily fluctuation over +/- 5 % RH should be avoided. recommended temperature and relative humidity [RH] for color and black and white materials [ISO 18911:2000, ISO 18918: 2000, ISO 18920:2000]16 Material Temperature in °C Relative humidity RH in % glass plate negatives ≤ 18 30 - 40 black and white film ≤ 21 20 - 30 black and white paper ≤ 18 30 - 50 chromogenic color film ≤ - 10 20 - 50 (Acetate) chromogenic color paper ≤2 30 - 40 dye destruction process ≤ 18 30 - 50 If a cold storage facility is used it is absolute essential to use the necessary acclimatization time in an acclimatization room to avoid damages caused by condensation water and different ratios of material extension (delamination damages). If no acclimatization room is available the photographic material can also be backed in an isolating container/ box and placed in the working room 24 h before use. Note: the acclimatization time extends with greater volume of the objects and larger temperature difference between cold storage and working room. 3. Exposure to direct sunlight or light sources containing high levels of ultraviolet radiation should be avoided. Tungsten and ultraviolet-free fluorescent lamps are recommended for viewing and exhibiting. The material in the Renbjør collection contains

mostly photographic objects, which are very sensitive to light. The amount of light for viewing and exhibition should be limited to the absolute minimum necessary. In most cases this is less than 50 Lux/ for one year exposure less than 12000 lx.h.17 To avoid delaminating damages when viewing, it is important to protect the sensitive (often multi-layer) color material from heat coming from light boards or viewing lamps. Special designed or modified â&#x20AC;&#x153;coldâ&#x20AC;? light boards, which protect the emulsion layer from heat damage, are recommended for viewing or duplicating. 4. The storage environment should be free of mould, pests, cigarette smoke, exhaust fumes, vapors of cleaning agents, and of peroxides, ozone, sulfur gases and other harmful gases originating from sources like scanners, copy machines, computers, etc. Working rooms with computers, scanners and copy machines are not appropriate storage rooms for image material (nor any other museum objects). The storage room should be exclusively designed for the storage of the photographic material. 5. For storage materials apply the same recommendations as for most other enclosures for photographic materials, namely that they should fulfill the ISO 18902:2001 and if possible they should have passed a P.A.T. [Photographic Activity Test]. In general this means that the enclosure material with direct contact to the print should have a neutral pH, the best materials are made from alpha-cellulose (lignin free cellulose fiber). Paper enclosures (but no glassine paper) are recommended for this purpose, polyester enclosures should if possible not be used because of the danger of ferro-typing. Exterior box-material should be made from buffered board. Prints should not be stored for long time in frames because of the harmful microclimate produced within the frame. Additionally, the framing material will in many cases not be an appropriate storage material [buffered boards in direct contact with the prints, wooden frames, tapes, etc.]. 6. All personnel should use cotton gloves while handling photographic materials.

What can be done? Conservation / Restoration The objects of the RenbjĂ¸r collection are in many different quality levels of condition and there are certainly possibilities for improvement. One part of future work in terms of preservation will be preventive conservation work. A lot of the work, such as changing enclosure material and dry cleaning, can be done by the staff of the Levanger museum. There are however objects in need of skilled conservation work for example restoration/ consolidation of emulsion layers and sealing of screen plates. This should be carried out with the aid of a professional photo conservator. On the photographic material seen in this survey the following conservation/ preservation steps should be executed in the nearest future: Cleaning Before/ during changing enclosure materials and other preservation efforts, all materials should be checked for mould and dust and maybe cleaned. If any sign of mould is found, a conservator should be contacted. For cleaning it is recommended to use a soft antistatic camelhair brush. Canned/pressured air should not be used because it can cause damage on loose emulsion layers. To avoid further loss of image material plates with loose emulsion layers should not be cleaned. Cleaning of such plates should be part of a future restoration project. Enclosure materials Again, all negatives, slides and color plates should be stored in pH neutral alpha cellulose enclosures. Polyester enclosures can be used provided right acclimatization. Appropriate amounts of slides and color plates, depending on size and weight, should be stored in closed archival boxes (Fig. 48) to prevent rapid climatic changes during transportation and to provide protection from air pollution. 35 mm material can also be stored in polyester enclosures, as long as drastic Fig. 48 temperature changes can be avoided, which are gathered in closed archival folders made from archival board (Fig. 49). Screen plates and glass plate negatives should be stored in folding envelopes with four flaps (Fig. 50). The four flap envelopes provide a more secure packing and unpacking of especially glass plates with loose or brittle emulsions. The appendix contains information (web-pages) concerning sources for special enclosure materials.

Fig. 49

Fig. 50 24

Conservation/ Restoration - on objects with glass corrosion, cracked glass supports, silver mirroring, mould damages, discoloration and color shift, finger prints, water damages, and brown spots, green spots, black spots in Autochromes Conservation/ restoration of the above mentioned damages will improve the condition of the photographic object only in some cases (glass corrosion, cracked glass supports, silver mirroring, and finger prints) and will often have only minor effect. Most of the damages (mould damages, discoloration and color shift on chromogenic materials, water damages, brown spots, green spots and black spots in Autochromes) have a more permanent nature, so responsible conservation work should aim at the stabilization of the objects condition. Chemical treatments, which are often recommended in older photo and conservation literature, may improve the visual properties of a few of the photographic images but will not enhance the stability. In addition, such treatments can/ will often cause greater damages and also total loss of the image information and should therefore not be used in a responsible museum environment. Conservation/ Restoration [Screen plates] Many of the screen plates have a serious delamination problem (loose and flaking emulsion layers) that may cause the loss of very important parts of image information. Prior to further handling and project-work, all color material with a delamination problem (screen plates and Pinatypi plates Fig. 23, 24) should be treated in a conservation laboratory with the purpose of consolidation of the emulsion layers. Most of the Autochrome and Agfa color plates have no cover glass or protective varnish, giving air and moisture direct access to the emulsion layers. This is one of the main reasons for the majority of damages like exfoliation, discoloration and green spots, on most of the screen plates. To increase the protection of the emulsions, after consolidation of the image layers, all screen plates should be sealed behind a cover glass (like advised already by LumiĂ¨re).18 Conservation/ Restoration [curling film support] As already mentioned, there can be several reasons for a curling film support. The deterioration of cellulose nitrate or acetate can cause change of dimension of the plastic material. A very hardened gelatin emulsion in addition to bad storage conditions with very low relative humidity and tight rolled storage can also be a reason. Some of the affected material may be treated in a conservation lab to bring back some of the original properties. But many of the early plastic emulsion carriers suffer surely under the typical dimensional changes which takes place during the deterioration process. To prevent loss of image information it would be a good idea to include this material in a duplication project (facsimile production).19

Facsimile production Photographic color materials are very sensitive materials in terms of light and environmental changes; the RenbjĂ¸r collection is a good example of that. To preserve this unique collection also for future generations and in the same time be able to exhibit in shorter and longer periods is a challenge. In order to avoid further deterioration and damages, preserve the original image information and to make exhibition possible, it is advisable to produce a set of facsimile images. The production of such facsimiles should be done by the staff museum photographer who has already extensive knowledge in handling and working with all kinds of contemporary and historic photographic material. For authenticity and permanence reasons, traditional photographic color material should be preferred before digital media. In a later stage the facsimile material can also be very useful for the production of digital files while the originals can remain in cold storage. For duplication work KODAK PROFESSIONAL EKTACHROME Duplicating Film EDUPE is recommended. This film material is available in a variety of roll and sheet sizes (see Kodak table) which make it perfect for the need of making transparency facsimiles. For the production of facsimile prints the very stabile Fuji Crystal Archive paper (best chromogenic paper at the time20) should be the chosen material. KODAK PROFESSIONAL EKTACHROME Duplicating Film EDUPE Sizes and catalog numbers may differ from country to country. See your dealer who supplies KODAK PROFESSIONAL Products. EDUPE Film replaced KODAK EKTACHROME Slide Duplicating Film / 5071, EKTACHROME Duplicating Films / 6121, Type K / 7121, and EKTACHROME SE Duplicating Film SO-366. Rolls mm x ft

Code/Spec No.

Acetate Base

135 - 36

EDUPE/-

5 mil (0.13 mm)

Cat No. 134 2641

35 x 100

EDUPE/SP663

195 2837

35 x 400

EDUPE/SP663

114 7461

35 x 1000

EDUPE/SP663

197 5358

46 x 100

EDUPE/SP446

122 1985

61.5 x 100

EDUPE/SP816

102 3035

70 x 100

EDUPE/SP481

813 7523

120 single (Japan only)

EDUPE/-

139 5268

Film Code

Acetate Base

EDUPE

8.2-mil (0.21 mm)

Sheets

Size

Cat No.

4 x 5 in.

8 x 10 in.

133 1941

8 x 10 in.

163 8444

13 x 18 cm

117 8169

802 4531 890 6943

Appendix

http://www.arkivprodukter.com/ http://www.klug-conservation.com/ http://www.museiservice.se/ http://www.monochrom.com http://www.archiv-box.de/ http://www.preservationequipment.co.uk

Illustrations/ Reproductions Title: Pinatypi transfer plates by Harald Renbjør, Renbjør collection, reproduction: Jens Gold. Fig. page 3: Harald Renbjør about 1910, color corrected detail of an Autochrome plate; Renbjør collection, reproduction: Jens Gold. Fig. 1,Microscope photography in Fig. 7, 8, 10, 11 and Fig. 12; Nils Torske, Levanger museum. Fig. 2 – 10, 15, 16, 17, 19, 22 – 47; reproduction: Jens Gold. Fig. 48, 49, 50 + the picture on page 27; Klug conservation – Germany, www.klug-conservation.com. Last picture on page 27: Preservation Equipments, UK, http://www.preservationequipment.co.uk. Fig. 13, MUTTER 1967: E. Mutter, Farbfotographie – Theorie und Praxis, Die wissenschaftliche und angewandte Photographie Band IV, Wien/New York 1967, 44. Fig. 14, HENDRIKS 1991: K. B. Hendriks, Fundamentals of Photograph Conservation: A Study Guide, Toronto 1991, 176. Fig. 18, MUTTER 1967: E. Mutter, Farbfotographie – Theorie und Praxis, Die wissenschaftliche und angewandte Photographie Band IV, Wien/New York 1967, 83. Fig. 20, MUTTER 1967: E. Mutter, Farbfotographie – Theorie und Praxis, Die wissenschaftliche und angewandte Photographie Band IV, Wien/New York 1967, 54. Fig. 21, MUTTER 1967: E. Mutter, Farbfotographie – Theorie und Praxis, Die wissenschaftliche und angewandte Photographie Band IV, Wien/New York 1967, 55. Table on page 26, Kodak: www.kodak.com. Source for all condition illustrations and reproduced photographic material in this paper was the Renbjør collection.

Bibliography COOTE 1993: J. H. Coote, The illustrated History of Colour Photography, 1993, 36, 84, 121 – 125. DOBRUSSKIN/ HESSE/ JÜRGENS/ POLLMEIER/ SCHMIDT 2001: S. Dobrusskin, W. Hesse, M. Jürgens, K. Pollmeier, M. Schmidt, Rundbrief Fotografie, Sonderheft 1, Faustregeln für die Fotoarchivierung, 4. Auflage, 2001, 32 - 33, 36 - 37, 81 – 83. HENDRIKS 1991: K. B. Hendriks, Fundamentals of Photograph Conservation: A Study Guide, Toronto 1991, 347-350. ICP - INTERNATIONAL CENTER OF PHOTOGRAPHY 1984: Encyclopaedia of Photography. KOSHOFER 1981: G. Koshofer, Farbfotografie Band 1 – 3, München 1981, Vol.1, 173 – 174, Vol. 2, 30. KRAUSE 1985: P. Krause, Preservation of Autochrome Plates in the Collection of the National Geographic Society, Journal of Imaging Science, New York 1985, 182 – 192. LAVÉDRINE / von WALDTHAUSEN 2002: B. Lavédrine & C. von Waldthausen, An Investigation into a Consolidation Treatment for Flaking Autochrome Plates, ICOM – CC 13th Triennial Meeting, Rio de Janeiro, Sep. 2002, 664 – 669. MUTTER 1967: E. Mutter, Farbfotographie – Theorie und Praxis, Die wissenschaftliche und angewandte Photographie Band IV, Wien/New York 1967, 30 – 92. NISHIMURA 2001: Doug Nishimura works as chemist and research scientist in the IMAGE PERMANENCE INSTITUTE AT THE ROCHESTER INSTITUTE OF TECHNOLOGY. He is internationally known as writer and lecturer in the field of photographic conservation and preservation. POLLAKOWSKI 1998: Dr. Goetz Pollakowski is a chemist, specialized in photochemistry; he has worked for the DEFA – Berlin/Potsdam and the Preservation Commission of the FIAF. He teaches photochemistry at the University for Applied Science in Berlin. TORSKE/ STALDVIK 2003: Nils Torske / Line Staldvik, Harald Renbjør - pioner i norsk fargefotografi - et bokprosjekt, Levanger 2003. 29

WILHELM 1993: Henry Wilhelm, The Permanence and Care of Color Photographs: Traditional and Digital Color Prints, Color Negatives, Slides, and Motion Pictures, Grinnell - Iowa 1993, 20 â&#x20AC;&#x201C; 27. WILHELM RESEARCH 2003: http://www.wilhelm-research.com/

Endnotes 1

TORSKE/ STALDVIK 2003, Harald Renbjør - Pioner i norsk fargefotografi - et bokprosjekt 2003

It is also possible do make direct black and white separation positives to save one step.

MUTTER 1967,30 - 76. COOTE 1993, 84.

MUTTER 1967,39. COOTE 1993, 36.

Encyclopaedia of Photography MUTTER 1967, 38 - 39.

Encyclopaedia of Photography

MUTTER 1967, 88 - 92.

MUTTER 1967, 82 – 83. COOTE 1993, 121 – 125.

MUTTER 1967, 54 – 55. KOSHOFER 1981, Vol.1, 173 – 174; Vol. 2, 30.

KRAUSE 1985, 182-192.

POLLAKOWSKI 1998, personal communication.

WILHELM 1993, 20 – 27.

NISHIMURA, ROCHESTER INSTITUTE OF TECHNOLOGY - IMAGE PERMANENCE INSTITUTE 2001, personal communication.

DOBRUSSKIN/ HESSE/ JÜRGENS/ POLLMEIER/ SCHMIDT 2001, 76-77.

KRAUSE 1985, 182-192. LAVÉDRINE / von WALDTHAUSEN 2002, 664 – 669.

HENDRIKS 347-350, 1991.

WILHELM RESEARCH 2001.