Photography has evolved through many processes since the early 19th century from that first daguerreotype to today's digital images. And the wide variety of images created using these different processes can be found in many collections. Some require more special handling than others. Each requires knowledge of the proper storage techniques. Following is a brief look at some of the most popular of these processes.
Develop a method of cataloguing and identifying prints and negatives for future reference. It is important to label items in a collection so that each image can be properly inventoried and identified over time. Care should be taken, however, to use safe implements for labeling. Always label photographs on the reverse. A soft, No. 2 pencil with a somewhat dull tip can be used for prints that have a paper surface backing. An All-Stabilio pencil or a blue photo marking pencil can be used for resin or plastic coated photographs. Do not press too hard when writing, as this will create an indentation on the front. For film and negatives, use a film marking pen. Do not write directly on the frames, but on the lead or a wide margin. A safer method is to mark the sleeve or the paper enclosure prior to inserting the film strip or negative. Do not use sticky notes or self-adhesive labels, as they will leave a residue that will discolor over time.
Handle all prints and negatives with anti-static gloves or cotton gloves to eliminate the possibility of damage from fingerprints or oils or of lint and dust clinging to the images.
Select the primary enclosure based on the usage. An image that will be handled often is better stored in a plastic enclosure for easy viewing. Use polyester, polypropylene, or polyethylene, which are all safe plastics for archival storage. Never store photos in vinyl.
An image that will not be referred to often should be stored in a paper enclosure for maximum protection against light. The most recent ISO standards advise storage of all types of photographs in buffered paper, although some archivists and curators prefer to use unbuffered materials for color prints, albumen prints, and cyanotypes. All paper enclosures should be acid-free and lignin-free.
Store photos in enclosures in sturdy, acid- and lignin-free boxes that match the size of the prints. When storing multiple sizes of prints together, put the largest photos on the bottom to avoid damaging smaller photos. To reduce cost and space usage, large photo collections can be stored without individual enclosures. Store those photos in boxes with interleaving paper, such as Permalife Bond Paper, between each photo.
The best storage environment for photographic materials is one that is cool, dark and dry. Following are the recommended temperature and humidity for different media:
If it is not possible to maintain these readings, be sure to place your photos in an area that is not subject to temperature extremes. A shelf in a dark closet on the main floor is often the best location available in a home.