All photographic prints should be stored at 77 degrees Fahrenheit (25 degrees Celsius) or less with 20-50 percent relative humidity. These conditions are based on the recommendations from experts in the industry and are consistent with ISO recommendations for medium term photographic storage. Other products, including StoryBooks, Page Prints and other digital prints, will also last longer under these conditions. To see what will happen under different conditions, the Preservation Calculator from the Image Permanence Institute is available at Calculators. This program is now compatible with the Widows Vista operating system.
The complete Tech Notes article with more details is available at tech-notes_20090304.