Silver Dye Bleach Photographs

Risks of Handling/Use

Generally, handling and use heightens the risk of damage to your materials, be it through neglectful handling (e.g. touching photo emulsion with bare hands) or irresponsible operation of access equipment. This is a risk posed by patrons and staff alike, intentional or not.

Handling and Collections Care

One of the easiest areas to implement protections for collections is through careful handling and sensible collections care. The unfettered use and handling of materials heightens the general risk of damage--be it through neglectful handling (e.g. touching photo emulsion with bare hands) or irresponsible operation of access equipment. Whether intentional or not, this is a risk posed by patrons and staff alike.

Examples of neglect, mishandling, and mismanagement include:

General Recommendations:

Additional Copies

The use of additional copies for reference or display purposes is highly recommended, particularly if the item is an original or valuable. This provides broader access to the content while also protecting the original document from user wear and tear or environmental factors.

Recommendations for care of original object:

To learn more about best practices for use and access, including resources for creating digital surrogates, see Use & Access in the User-Manual.

Orientation in Storage

Store vertically with dividers between each print. May also be stored horizontally, especially large prints. Enclosures and folders may be stored in hanging files or archival storage boxes.

Storage Container

Dye-transfer prints should be stored in nonbuffered storage materials, since the prints are stabilized at an acid pH (acetic acid bath). Each print should have its own enclosure to protect it from dust, handling damage, and changes in environmental conditions.

This enclosure may be a paper (archival-quality, acid-free) or plastic (uncoated polyester, polyethylene, polypropylene, cellulose triacetate) sleeve, envelope, or wrapper. Include a rigid secondary support within this enclosure. Position image material away from seams in paper enclosures. Seams should be on the sides of the enclosure, not down its center. Enclosures should be stored in hanging file folders or archival storage boxes. Wood cabinets should be avoided. Enameled steel, stainless steel, or anodized aluminum are preferred.

All storage materials should pass the Photographic Activity Test (PAT) as specified in ISO Standard 18916:2007.


If your item has any kind of labeling on the container, the item itself, or any related material, we highly recommend that you return to the Basic Info section and enter this information in the appropriate field(s).

Labeling on a container or on the item itself, if it is in fact correct, can offer important clues about its content. If you are replacing a container that holds labeling information, it is important to transfer this information to the new container or label. Be sure to copy down any titles, dates, or other data found on these items and save your notes. Container labels should be used with caution as they are frequently reused or easily switched by accident.

For sleeves and folders especially, remember that it's generally best to label with a no. 2 pencil. If ink must be used (i.e. on a plastic enclosure), use an archival pigment-ink pen (e.g. Micron).

Physical Damage

Regardless of its acidity and inherent vice, all paper is susceptible to tearing and other forms of mechanical damage. Fiber-based prints will have a tendency to curl, usually as a result of fluctuating humidity.

If on RC paper or acetate, support instability will be the weakest link in terms of photographic permanence. Polyester supports are low risk and quite stable. Care should be taken when handling prints to avoid abrading or placing fingerprints on the glossy surface. Very humid or wet environments may cause considerable deformation and delamination.

Mold / Pest Damage

The gelatin binder of a photographic emulsion is an especially good nutrient for mold. If your item is exhibiting white or brown patches or if you see a lattice-like growth along the edges, you are most likely viewing mold. Negatives stored in hot, humid environments are most vulnerable to mold, mildew, and fungus contamination. Mold will typically damage the edges of photographic material first. If mold has eaten into the emulsion, the item will be noticeably and irreparably damaged, exhibiting feathery-like distortions or dull spots on the image. Mold can be removed through cleaning and then storing the items in a cold, dry environment, but this should be done responsibly.

Pests like insects and rodents tend to like paper and textile materials. High humidity (higher than 68% RH) promotes mold growth and insect infestation, both of which can cause permanent damage. When assessing the exposure of your collections to pests, it is necessary to look not just at the materials themselves and their containers, but also at the larger environment. Insects and rodents tend to leave droppings in areas they inhabit. Insects tend to leave behind a substance called frass, which is the undigested fibers from paper. If you see droppings and/or frass in the storage area, it is a strong sign that your materials are being exposed to pests. Small, irregular holes in paper-based enclosures are also a sign that pests have attacked your materials.

Some tips for reducing your materials' exposure to pests are to refrain from eating anywhere near your collections materials. Crumbs and food waste draw pests, so eat far from your collections. Another tip applying to both pests and mold is to be cautious about donated materials when you receive them. Pests and mold can hitch a ride into your facility on these materials, so having a good, clean staging area where you can inspect donated items for, among other things, pest and mold evidence can help you reduce your storage environments' exposure to both.

Support Type

Silver dye-bleach prints are on either polyester, resin-coated(RC) paper, or acetate.


Polyester supports have strength and provide excellent image stability. Polyester is inert, considered archival, and has a life-expectancy of 500+ years under proper storage conditions.

Resin-coated (RC) Paper

Resin-coated supports curl and will embrittle and crack due to light exposure and fluctuating relative humidity. Coated papers are generally more sensitive to water and abrasion than uncoated papers.


Acetate supports will yellow and eventually exhibit vinegar syndrome. One of the key signs that an acetate print is degrading is the presence of a vinegar smell. This degradation results from the chemical breakdown of the acetate into acetic acid and is known as "vinegar syndrome." The odor can be very strong and unmistakable.

Although the vinegar odor is often the most obvious sign that an acetate film is degrading, it is not the only sign. Acetate film that is degrading becomes brittle. The film loses its suppleness and does not gently curve around the core or reel; instead, the film appears jagged or "spoked." The film base will also shrink. To help prevent or slow acetate decay, you can place molecular sieves in your film cans. These desiccants will help absorb acetic acid and moisture in a sealed film can.

The PSAP has also adapted the Image Permanence Institute's A-D Strip scoring method to rate vinegar syndrome in acetate film. These strips, developed by the Image Permanence Institute, change color based upon the level of acidic vapor detected. A-D strips are an excellent way to score and monitor vinegar syndrome; they can give you a finer level of assessment beyond visual and olfactory cues. Using A-D Strips in conjunction with the PSAP can make your vinegar syndrome assessment much more accurate. For more information about A-D Strips, click here:

The following is a guide to rating acetate decay (vinegar syndrome):

No Deterioration. This item is suffering from no acetate decay.

Deterioration Starting. Acetate decay is starting. This print should be moved to cold storage if possible and monitored. The print is flexible, with little (less than 1%) to no apparent shrinkage. There may be a very faint vinegar smell.

Actively Deteriorating. This print is actively deteriorating. It should be moved to cold storage if possible and duplicated. The print will have a stronger vinegar odor and may exhibit shrinkage (between .8 to 2%). The print will also exhibit some waviness along the edges; it may curl slightly and resist lying flat.

Critical Deterioration. This print is exhibiting shrinkage and warping. It may be difficult or impossible to handle without damaging it. The print should be frozen if possible. The vinegar odor is unmistakable. The emulsion layer looks cracked and may already have separated from the base. White powder may be visible on the edges of the print.

In order to slow or stop acetate decay, items should be stored in cold to frozen conditions (32–40°F and less than 32°F, respectively). Once the decay starts, it cannot be reversed. If an item is discovered to be acidic and succumbing to vinegar syndrome, it should be separated from other "healthy" items as it can "infect" the other items.

See Acetate Decay in the Film Decay section for more.

Paper Decay

Paper is sensitive to light and water exposure, high humidity, and high heat. Exposure to light and/or heat will accelerate deterioration in the form of yellowing and sometimes embrittlement.

Acidic paper (pH below 7.0) commonly exhibits both deteriorative traits. Colored media on the paper support will fade rapidly. Water exposure can ultimately lead to desiccated or brittle paper, making it more easily torn or damaged through handling. Fluctuating temperature and RH may result in warping and cockling of the paper surface. High humidity (higher than 68% RH) promotes mold growth and insect infestation, both of which can cause permanent damage.

According to a study by the Library of Congress, even pH neutral papers will become increasingly acidic over time. This is due to the fact that cellulose naturally generates acids as it ages. Papers, including book leaves, that are darker and more brittle along their edges than center demonstrate an absorption of airborne pollutants that have formed acids.

Soil and dust may become ground into paper fibers, permanently soiling or staining the paper surface. Foxing is a common form of paper deterioration, which manifests as reddish-brown spots or blotches that appear embedded in the paper surface. Foxing is caused by a number of factors but is commonly spurred along by high humidity.

Fading, Staining, and Discoloration

Silver dye-bleach prints are highly sensitive to water, pollutants, abrasion, and fingerprints. Wetting may cause distortion, delamination, and dye migration. Because silver dye-bleach prints are produced using azo dyes, which are relatively light stable, image quality is high and will exhibit little to no image fading.

However, long term display should be avoided as prolonged light exposure and airborne pollutants will eventually cause color to shift.