Photographs document history in a special way, and as we collect them, they complement our family papers, providing a graphic reality and a unique understanding of our family's past.

A relatively new process, photography was developed in France and England by the 1840s. This distinctive method of documentation spread quickly throughout the world, spurred by the industrial revolution and the Civil War. During the same period, the general public also discovered the benefit of documenting events or family importance.

A photographic print or negative consists of a base material; coated with a light sensitive emulation. Over the years, base materials and emulations have changed. None the less, photographs remain physically and chemically more complex than paper materials. They are susceptible to deterioration by chemicals left over from processing or careless handling. Light sensitive emulsions are also subject to fading when exposed to light and the instability of color dyes rend all color photographs impermanent.

Preserving your family photographs requires more than simply placing them in a shoe box or any convenient album. Often the materials of which these items are constructed place photographs at risk.

• Avoid fluctuation in temperature and humidity: High levels of temperature and relative humidity accelerate destructive chemical reactions and encourage mold growth that feed on photographic emulsions. The optimal temperature is 68 degrees F and 35 to 40% relative humidity.

• Promote cleanliness: In addition to causing stains, dirt, food, and drinks attract vermin which feed on photographs.

• Avoid direct light sources: Photographic images are extremely light sensitive. Exposure to light should be closely monitored and direct sources of light avoided.

• Promote good storage practices: Use only archival quality materials to store your photographs. Avoid the use of "magnetic" or self stick photo albums. These, along with plain cardboard, wooden, or metal boxes can cause serious damage to your photographs. Never store photographs in a basement or attic.

• Hold photographs and negatives by the edge: Avoid touching the emulsion surface.

• Identification is important: Use a soft pencil and mark on the back edges. Excessive pressure will leave an imprint on the front side. (New photographic prints will not take pencil marking. For them, you need a photo pen, which you can find at most photographic stores or office supply stores.) Never use a ballpoint pen.

• Storing Photographs: Avoid using pressure sensitive tapes: Pressure sensitive tapes, along with most adhesives, rubber bands, and metal clips can damage photographs and cause severe staining.

• Frame carefully: At least one layer of acid-free mat board should separate the photograph from the glass. High levels of relative humidity can cause photographic emulsions to stick to the glass in a picture frame.

Source: Bureau of Archives and Records Management, Tallahassee, Florida
Published in The Legacy, March 1996 Issue, Number 1.