CoPAR Bulletin 12: Basic Steps in Preservation of Photographs

Basic Steps in Preservation of Photographs
by Willow Roberts Powers

Photographs are an integral part of anthropological records, and photo documentation can often consist of hundreds — even thousands — of images. The sheer number of items and the changes in format and technology over time make preservation seem challenging. Organization and good basic housing and storage are the keys to preservation.

Organization

Good organization is the first step in preservation, and preservation of information that goes with an image is as critical as preservation of the image itself. Photographs, though used singly, come in sets, and these sets reflect the context of their creation.

Organization is also called arrangement. There is a subtle difference: organization tends to reflect the context of creation (by project, date, geographical location, etc), whereas arrangement may reflect an active, analytical process by the creator (setting forth evidence, comparison, authentication; or for publication, exhibit, etc.). Each has its own merits, and it is worth mentioning implications.

Typically, photographic images are organized by the research, fieldwork and/or project in which they were created. Consistent documentation of a project requires organization by whatever principles are relevant (year, geographical location, community, family, activity, site, etc). Organization should include documentation for the images, in groups or individually, usually done as the photographs are taken. Both the organization and the documentation help to make a systematic link between images and field notes, and between prints and negatives. It may not indicate your use and analysis of photographs: these tend to be reflected in reports and publications.

Often, photographic images are arranged by use, sometimes by default: slides are arranged for lectures, photos for publications, content analysis, exhibits, etc. Such arrangement may illustrate your ideas and analysis, later publications and continued use; it may not make it so easy to connect prints with negatives, or images with their original context of creation and documentation.

Photographic formats

Variety of photographic formats is typical in collections. You may create images in several different photographic formats, both over time, and within each project: 35 mm prints, 35 mm. negatives, 4×5 transparencies, slides, enlarged prints, etc. It is best — and easiest — to keep formats together, where possible, identifying each format.

Increasingly, digital cameras are being used, and images produced through computers. It is even more important to print these out and document the hard copy. For information on digital technology, see CoPAR’s Bulletin on Managing Electronic Records.

Basic storage

Simple, basic preservation storage of your photographs is useful for as long as you hold and use them. If and when you turn your papers and photographs over to an archives, professional staff will evaluate the need to rehouse the collection in professional quality storage materials.

Cleanliness is of course primary: clean folders, clean, new boxes, envelopes and sleeves. If possible, buy acid-free materials from an archival supplier (supply catalogues can be found in Bulletin No. 11) but ordinary office supplies will suffice if they are brand new.

Do not use labels, on prints (glue will aid deterioration) or on folders (they will fall off).
Write all information, preferably in pencil.

Heat, moisture, and light are enemies of all photographic materials, as are sticky liquids and crumbs, insects and other forages. All boxes should have lids.

Never use PVC (polyvinyl chloride) plastic sleeves. This is a heavier, stiff plastic with a distinct plastic odor. These are not sold in archival catalogues, and sleeves are now uncommon but may be already in use in older papers. The plastic will bind to the photographic print over time.

Do not use plastic binders. Many 3 ring binders are made of PVC plastic, and are not recommended: they give off a gas which contributes to considerable deterioration of photographs (and paper). Never use PVC sleeves — heavy plastic with a distinct odor.

Negatives should be stored in a cool, dry place. They need to be stored in sleeves or envelopes. Negatives scratch easily, and carry fingerprints forever. They should be separated; do not store them together without sleeves. In a pinch, clean new sheets of paper can be folded to hold negatives.

There are many different kinds of negatives, and sleeves appropriate for all. If you have older negatives (before 1948) they may be nitrate or acetate, and yo will need to ask the advice of a photo archivist, museum conservator, or photographic conservator. Recognizing such negatives requires either knowledge or special tests. Museums, state or other archives, or university special collections are good places to go for advice or referrals.

• Nitrate and acetate negatives should always be sleeved in acid-free, unbuffered paper, never in plastic.
• All safety negatives (color or black and white) can be stored in good quality polyester sleeves.
• Acid free paper sleeves are always acceptable for all negatives; old manila type sleeves (often used for photographs) are not good —they are highly acidic.

Professional archival catalogues carry a very wide variety of sleeves.

• ‘Page preservers’ – 8×10 polyester pages with channels or pockets for negatives (also for slides or prints: carried by catalogues and most photographic stores, usually in an acceptable plastic, at least for the short term; least expensive method.
• Archival sleeve-and-box sets: carried by all major catalogues, which are more expensive, very easy to use and helpful for good identification.
• Acid free paper sleeves for negatives in formats other than 35 mm.

Note: similar format sleeves in which negatives come from the processor are low quality, but acceptable for interim storage.

Ideally, sleeved negatives should be stored unfolded, in file folders.

Slides can be either stored in polyester page preservers, or in any of the variety of slide boxes. They should be kept clean, dust free, and out of the light and heat. Slides are meant to be used; exposure to the heat and light of the projector will, however, contribute to some deterioration over time. As makers of film experimented with color stability, slides from particular dates can be subject to color shifts no matter how they are stored or whether they are used or not.
Document all slides – best done on the slide, in pencil.

Prints can be sleeved in a variety of methods, including albums. Prints are the ‘use copy’ of a negative, and it is not essential that they be sleeved, but they should still be taken care of. The decision on whether to sleeve or not to sleeve will derive from factors of: cost, age — and perhaps rarity — of the print. Sleeve in:

• Polyester page preservers, for different sized prints (least expensive, holds several prints and thus takes up less space)
• Polypropylene sleeves in different sizes for individual prints (archivally sound, moderately price
• Mylar sleeves in a few different sizes for individual prints (best archival material, highest price)
• Paper sleeves are not recommended as the print will have to be taken out to be seen.
• Place prints (sleeved or unsleeved) in clean file folders (acid free is best) or even in 8×10″ envelopes (acid free is best).

Albums are a good way to display and document sets of prints.

• Avoid those albums which have waxed pages (‘magnetic’ albums) on which prints are placed. The prints will be permanently adhered to the page, and the glue is highly acidic and contributes to deterioration (it will also discolor over time).
• Avoid glue and black, or other colored, highly acidic paper
• Do not use tape to hold images in place. Photo corners can be used, or page preservers, or cut slits in the base paper into which you can slip the corners of the print.

Photographic stores carry albums which, while not archival quality are not harmful to photos:

• Albums with plastic or paper with plastic sleeves; acceptable for interim, non-professional storage.
• Albums with high quality plastic and acid free paper pages from archival catalogues.

Digital prints may also be sleeved; they should be treated like traditional photographic formats. The paper on which these are printed, and the inks used, distinguish them from traditional photographs. Longevity of many high quality printers (see CoPAR Bulletin No. 14) have been found to produce long lasting copies, and the stability of digital prints continues to be tested and will improve.

The only issue with digital images is not preservation so much as documentation: since these images can be manipulated and altered it is useful to document whether this is an original, or a manipulated document. Some projects, when documenting photographs on computer databases, will include ‘digital’ as a category to be noted.

Moving Image Film

Moving image film requires similar storage to negatives: clean, cold (the colder the better) and dark. Store the reel flat – the film, wound on a core, is actually on edge. Archival plastic canisters are sold in supply catalogues, but original containers are adequate for interim storage. Do not attempt to run an old film (even your own) on any kind of equipment. The film may have shrunk, and the probability of damaging or destroying it are very high.

If you have, or are given, old film, look at it. Is it curling, breaking warped? Has it crystallized on the surface? Is there brown powder inside the can? Can you smell something acrid? If the answer to any of these questions is ‘yes’ – you need help. Contact a good archival institution and ask for guidance, or look up the Image Permanence institute on the Web. Older moving image film (before about 1940) can be nitrate, and should be checked. If it is nitrate and if it is stored in metal canisters, the film must be removed and rehoused in archival canisters. In this case too you may want to ask the advice of a preservation archivist.

Document the reel: copy whatever is written on the original canister — which may not be accurate — and add your own comments (‘rehoused October 2002’). Typically, when writing old information on new containers or folders, place it in quotation marks; this indicates, precisely, a quote. You, or whoever else reads the information, will know it comes from another source.

Identifying images

Identification and documentation can be done in a number of ways.

• Write on forms or notes to accompany prints – usually prints are then numbered; use a pencil (not a ballpoint or felt tipped pen). On modern wax coated prints, use a ‘Prismacolor’ brand soft blue pencil, available in most art stores. Film pens can be used, but the ink may show through the print.
• Write on the plastic sleeves containing images – use a special film pen (also for numbering negatives)
• Write on the folders in which the images are placed – do not use labels (which fall off easily); pencil lasts better than ballpoint or pen.
• Write on the edges of slide frames – in pencil or pen.
• Do not use very sharp pencils on prints – they will imprint the photograph.
• Do not use ballpoint, or felt tipped pens, both of which will smear.
• Maintain the organization – replace negatives or prints to their original files; if removing negatives or prints from a folder, make notes, or write on the print or negative, to identify where it came from.
• If there is old information, on envelopes or slips of paper accompanying the image, make sure it accompanies (or is written on) the print. If rewriting old information, put it in quotation marks; if possible identify the source.
• Place your own comments on other people’s photographs in square brackets and write your name and the date.

Some tips:

Hold prints and negatives by the edges; fingerprints leave permanent marks.

Never write directly on the face of a print or negative.

Pencil lasts better than pens.

Ballpoint pens smear.

Felt tipped pens ‘bleed’ through prints, or mark them.

Keep strips of 35 mm. negatives in strips – never cut out one frame. It is difficult, if not impossible, to make a print from it.

Keep prints and negatives out of sunlight, heat, and damp.

Keep negatives sleeved – even the sleeves in which they are returned from processing are acceptable.

Keep single format negatives sleeved singly to prevent scratching.

Keep groups of negatives together, in a file or even an envelope.

Do not use rubber bands or paper clips on prints or negatives.

If possible, and especially if you do not have the negatives, keep prints sleeved.

Photocopies, digital images, etc, are excellent for use, duplication for filing, and cross reference.

If you make many copies of an image (photocopies, digital images, etc) make sure to maintain either the negative or one good print as an original — for identification, copyright, and reference.

Often collections incorporate photographs taken by others: be sure to note this, especially
if these come from another archival collection.

Prints and negatives are separately housed and stored in professional archives. However,
do not separate yours until you have devised a system to connect prints to their negatives. An easy way to do this is to sleeve them appropriately and keep them in identically labeled folders.

Simple identification systems are always best. Many people keep a record as they take
photographs, and have a system of numbering their rolls with, for example, a project acronym, a date, and a roll number; prints will have this number plus the negative frame number. However, numbering every image is extremely time consuming. Numbering or naming groups of images is more manageable. The research may determine your decisions on how to best design documentation. Whatever system you use, keep it consistent within a project or a group of images. It does not matter if each project or group has a different system.

Archival supplies and supply catalogues

There is a large range of materials sold in archival catalogues, and selecting the right item can be confusing. Archival catalogues provide supplies in a variety of materials, for a variety of purposes, and not all are designed for preservation. Look for the term “preservation materials” or “archival quality.” In plastics, polypropylene is acceptable, vinyl is not, plasticizers are not, PVC is not. Good suppliers will have staff who can give information on materials.

In the last resort, if you have loose negatives, clean white envelopes and folded paper (much of today’s sheet paper is acid free) can be used for negatives. Separate negatives so that they do not scratch each other. Document everything.

References and Resources (See also CoPAR Bulletin No. 11 for more details)

Archival supply catalogues:

Gaylord Brothers (Syracuse, NY): 1-800-448-6160

Hollinger (Fredericksburg, VA): 1-800-634-0491

Light Impressions (Brea, CA): 1-800-828-6216

Metal Edge West (Commerce, CA): 1-800-862-2228

University Products (Holyoke, MA): 1-800-628-1912

A good source for albums in archivally sound materials (note that their catalogues include other materials) and reasonable prices:

Century Photo Products: 1-800-767-0777

For help with films and digital images:

Image Permanence Institute: www.rit.edu
Rochester Institute of Technology,
70 Lomb Memorial Drive, Rochester, NY 14623-5604
Phone: 585-475-7230 or 5199. ipiwww@rit.edu

The Society of American Archivists has excellent guides. The guide for photographs is:

Henry Wilhelm, 1993: The Permanence and Care of Color Photographs: Traditional
and Digital Color Prints, Color Negatives, Slides, and Motion Pictures. Grinnell, Iowa; Preservation Publishing Company.

An interesting reference to some of the conceptual issues with photographs (and thus their organization and documentation) is:

Michael S. Ball and Gregory Smith (1992): Analyzing Visual Data (Sage Publications)