Identifying Photographs
Photographic prints can be made by a variety of processes and process informs storage and handling recommendations. The following institutions have put together useful references for identifying photographs:
- Northeast Document Conservation Center, Types of Photographs
- Victoria and Albert Museum, Photographic Processes
General Care and Handling of Photographs
The information on this page covers photographic prints from all eras of photography and photographic negatives, but not digital image files.
Taking care when handling any collection item is one of the more effective, cost-efficient, and easily achieved preservation measures.
Take proper care when handling photographic materials by:
- Having clean hands and wearing non-scratching, microfiber or nitrile gloves; having a clean work area
- Keeping food and drink away
- Not marking photographs, even on the back side
- Not using paper clips or other fasteners to mark or organize prints
- Not using rubber bands, self-adhesive tape, and/or glue on photographic materials
General Guidelines for the Proper Storage of Photographs and Negatives
Good storage is arguably the most important preservation measure for photographic prints and negatives:
- A relatively dry* (30-40% relative humidity), cool** (room temperature or below), clean, and stable environment (avoid attics, basements, and other locations with high risk of leaks and environmental extremes)
- Minimal exposure to all kinds of light; no exposure to direct or intense light; use duplicate slides in light projectors
- Distance from radiators and vents
- Minimal exposure to industrial (particularly sulfur-containing) atmospheric pollutants
- Protective enclosures within a box***
* Relative humidity is the single most important factor in preserving most photographic prints.
** For contemporary color photographs and for film negatives, however, temperature is the controlling factor affecting stability. Storage at low temperatures (40°F or below) is recommended. Appropriate enclosures for cold storage are available from various vendors.
*** Suitable protective enclosures for photographic prints and negatives are made of plastic or paper that meet certain specifications:
- Paper enclosures must be acid-free, lignin-free, and are available in both alkaline buffered (pH 8.5) and unbuffered (neutral, pH 7) stock. Storage materials must pass the ANSI Photographic Activity Test (PAT) which is noted in supplier's catalogs. Buffered paper enclosures are recommended for brittle prints that have been mounted onto poor quality secondary supports and for deteriorated film-base negatives. Buffered enclosures are not recommended for contemporary color materials. Paper enclosures minimize unnecessary light exposure; are porous; easy to label with pencil; and are relatively inexpensive.
- Suitable plastic enclosures are made of uncoated polyester film, uncoated cellulose triacetate, polyethylene, and polypropylene. Note: Photographic emulsions may stick to the slick plastic surfaces of these storage materials at high relative humidity (RH). Plastic enclosures must not be used for glass plate, nitrate, or acetate-based negatives.
Prints of historic value should be matted with acid-free rag or museum board for protection. Adhesives should not touch the print. Matting should be done by an experienced framer or under the direction of a conservator.
Store all prints and negatives (whether matted or in paper or plastic enclosures) in acid-free boxes. If possible, keep negatives separate from print materials. Store color transparencies/slides in acid-free cardstock boxes or metal boxes with a baked-on enamel finish or in polypropylene slide pages. For more information about storage of negatives, see Motion Picture Film
Protect cased photographs (e.g., daguerreotypes, ambrotypes, and tintypes) in acid-free paper envelopes and store flat; keep loose tintypes in polyester sleeves, or, if flaking is present, in paper enclosures.
Storage of family photographs in albums is often desirable and many commercially available albums use archival-quality materials. Avoid albums with colored pages and "magnetic" or "no stick" albums.
Dealing with Condition Problems
For condition problems that are insufficiently addressed by the measures outlined above, conservation treatment by a photograph conservator may be necessary.
The national professional association for conservators, the American Institute for Conservation of Historic and Artistic Works (AIC), maintains an online directory for finding a conservator by specialty and geographic location and provides information on how to choose a conservator. In addition, AIC also offers guidelines for the care of collections beyond library materials.
References and Selected Further Reading:
Image Permanence Institute (IPI) Storage Guides: Storage Guide for Color Photographic Materials and IPI Guide to Preservation of Digitally-Printed Photographs
International Federation of Library Associations and Institutions (IFLA) Strategic Programme on Preservation and Conservation, Care, Handling, and Storage of Photographs: Information Leaflet, [Información en español], Standards, Bibliography
Northeast Document Conservation Center, Preservation Leaflets -- 5. Photographs
Where can I buy preservation supplies?
Paul Messier, Preserving Your Collection of Film-Based Photographic Negatives
Eaton, George T. Conservation of Photographs. Kodak Publication, no. F-40. Rochester, NY: Eastman Kodak Co., 1985.
Keefe, Laurence E., Jr. and Dennis Inch. The Life of a Photograph: Archival Processing, Matting, Framing and Storage. Boston: Focal Press, c1984.
Much of the content on this page was prepared by Debbie Hess Norris, Photographic Conservator and Henry Francis DuPont Chair in Fine Arts, Winterthur/University of Delaware Program in Art Conservation.
[Additional excerpts from Collections Care: Preserving and Protecting Your Art and Other Collectibles, The National Committee to Save America's Cultural Collections, New York: Harry N. Abrams, Incorporated, 1992.]
The preservation procedures described here have been used by the Library of Congress in the care of its collections and are considered suitable by the Library as described; however, the Library will not be responsible for damage to your collection should damage result from the use of these procedures.
