The best possible storage environment for photos is a cool, dry place. Also paramount in the pursuit of perfect preservation is low-humidity storage. When displaying original images, take care. Most 19th-century images and most color photographs are vulnerable to light damage. Photos can be framed with a window mat that prevents direct contact of the photo emulsion layer and the glass so the photo does not adhere to the glass.
Visible light cause some damage, but most is caused by ultraviolet light.
Ultraviolet filtering glazing, such as Plexiglas UF3 or Acrylite OP1, can be used in place of regular glass to lessen ultraviolet exposure. A better, and sometimes more cost-effective technique, is to have originals copied and display good quality replicas of facsimile copies instead. Use individual enclosures within the storage unit such as folders or envelopes of archival quality materials. A good example of what should be avoid is the commonly available magnetic photographic album. Often these have acidic reactive cardstock pages coated with low-tack, pressure sensitive adhesive.