http://www.archives.gov/preservation/formats/photographs.html
I've heard that color photos fade. What can be done to stop the fading?
Yes, color photographs do fade. Unfortunately, the color dyes used in the image irreversibly decay with time. Light increases fading. Fading increases with the brightness of the light and the length of time in the light. When displayed, photos should be kept away from direct sunlight or bright lamps that are left on constantly.
Heat also increases fading, even at moderate temperatures, such as 70-75F, found in homes. At these temperatures, fading always occurs, even in the dark! Color photos will last longer if stored in the dark, in a cool dry location. However, only storage at cold temperatures can slow this irreversible decay process to a near stop. Cold storage is not practical for most people and can even cause more immediate damage if used improperly. Frost-free freezers can be used as long as special enclosures and handling procedures are followed (see Cold Storage Handling Guidelines for Photographs).
In recent years, since the mid-1980s and especially since 1990, the major photographic manufacturers have developed more stable dyes for color photographs, including the type of photographic paper used for snapshots. The good news is that these modern photographic prints will only fade a little over a lifetime, or even in 100 years, if kept in average home conditions. When displayed in moderate light conditions, slight fading might occur in 25 to 50 years. Remember that moderate light conditions do not include direct sunlight or bright spotlights! Previous to the mid-1980s, color photos faded dramatically in a few years when displayed even in moderate light, or even after 10 to 20 years when stored in boxes and albums. The other good news is that Kodachrome slides and transparencies always had stable dyes and will last decades with very little fading if they are not left in a projector for long periods. Even 60 year old Kodachrome slides look nearly unfaded. Cibachrome (now called Ilfochrome) photos always had good color dye stability, too. The bad news is that your older family photos and favorite portraits, Ektachrome slides, and other important color photos, are probably already faded. If you have selected the most important family photographs, those you hope to have for your lifetime or future generations, they should be copied now and printed onto the more stable color photograph papers (see: Where can I find sources for duplicating/copying historical photographs?). Faded color photographs also can now be scanned into a computer and digitally enhanced to restore the faded dyes to near original appearance, then printed onto the more stable photographic papers. Avoid copy prints made on computer printer paper, as these fade even faster than old color photos and are unusually sensitive to water!
