Putting It Into Practice

Evaluating Your Collections

Photographic Prints

Older rolled photographs can be difficult to unroll without damaging them; always consult a conservator if in doubt.

The most common types of photographic prints found in cultural institutions are cased photographs, albumen prints, silver gelatin prints, and modern color photographs. These may be stored with documents in files, in boxes or albums, or even loose in drawers.

As you have seen in this session, different types of photographic processes have specific vulnerabilities. However, there are some major categories of damage to photographs that you may observe within your collection. As with paper documents, photographic prints are subject to physical damage such as tears, creases, dog-eared corners, and mold or insect attack. Special concerns for photographs are abrasion and scratching of emulsions (binders), cracking emulsions, emulsions that are peeling away from the support layer, and indentations or staining caused by writing on the back of photographs.

Damage to this photograph has been caused in large part by the brittle and acidic board on which it was mounted.

Chemical damage to photographs may manifest itself in black and white images through fading of the image, loss of image detail, yellowing of the image, silver mirroring of shadow areas of the image, and/or staining. For color prints, color change and fading are the primary results of deterioration.

Rolled photographs are often found in collections. As with documents, these should not be unrolled if it seems this may cause damage; a conservator should be consulted. Photographs mounted on acidic boards are also common (these are frequently albumen prints, which tend to curl up if not mounted). There is often physical damage to the board and chemical damage to the photograph.

Photograph albums pose additional problems, since the albums themselves may damage the photographs. Many older albums have acidic pages that can accelerate photograph deterioration. Adhesives used to attach photographs often cause staining and sometimes fail, leaving the photograph unattached. Modern "magnetic" albums in fact use adhesive to hold the photograph to the page; this adhesive darkens and stains photographs over time. Modern albums with plastic pages made from polyvinyl chloride (PVC) also accelerate photograph deterioration. Polyester, polypropylene, and polyethylene are the only acceptable plastics for photo album pages.