This is advice from the US Library of Congress
- Relative humidity is the single most important factor in preserving most photographic materials. Relative humidity levels above 60% will accelerate deterioration. Low and fluctuating humidity may also damage them. Conditions of around 68° F and 30-40% relative humidity are appropriate and easiest to maintain in enclosed areas, such as an interior closet or an air-conditioned room — not in an attic or basement.
- Temperature is the controlling factor in the stability of contemporary color photographs. Storage at low temperatures (40°F or below) is recommended. Appropriate enclosures for cold storage are available from various vendors.
- Exposure to visible and ultraviolet (UV) light is potentially damaging to photographs. Extended display of photographs is not recommended; however if they must be displayed, use UV-filtering plastic or glass in framing. Exposure of color slides to the light in the projector should be kept to a minimum. Use duplicate slides instead.
- Atmospheric pollutants, particularly sulfur compounds, will cause black and white images to fade and discolor. Gas by-products given off by fresh paint fumes, plywood, deteriorated cardboard and many cleaning supplies may cause accelerated image deterioration. Storage in non-acidic containers is recommended.
Handling Photographic Materials:
- Avoid touching fragile photographic materials; salts in human perspiration may damage surfaces. Wear clean cotton gloves if possible when handling negatives and prints.
Storage of Photographic Materials:
- House photos in protective enclosures to keep out gritty dirt and dust which can abrade images, retain moisture, and deposit contaminants. Avoid and/or remove materials such as acidic paper or cardboard, polyvinyl chloride (PVC) plastic, rubber bands, paper clips, and pressure-sensitive tapes and rubber cement. Suitable storage materials should be made of plastic or paper, and free of sulfur, acids, and peroxides.
- Paper enclosures must be acid-free, lignin-free, and are available in both buffered (alkaline, pH 8.5) and unbuffered (neutral, pH 7) stock. Buffered paper enclosures are recommended for brittle prints that have been mounted onto poor-quality secondary mounts and deteriorated film-base negatives. Buffered enclosures are not recommended for contemporary color materials. Paper enclosures are opaque, thus preventing unnecessary light exposure; porous; easy to label in pencil; and relatively inexpensive.
- Suitable plastic enclosures are uncoated polyester film, uncoated cellulose triacetate, polyethylene, and polypropylene. Note: Photographic emulsions may stick to the slick plastic surface at high relative humidity (RH); the RH must remain below 80% or do not use plastic enclosures. 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.
- Store all prints and negatives that are matted or placed in paper or plastic enclosures in acid-free boxes. If possible, keep negatives separate from print materials. Store color transparencies/slides in acid-free or metal boxes with a baked-on enamel finish or in polypropylene slide pages. Commonly available PVC slide pages, easily identified by their strong plastic odor, should never be used because of their extreme chemical reactivity.
- Place early miniature-cased photographs, including daguerreotypes, ambrotypes and tintypes, carefully into acid-free paper envelopes and house 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 utilize archival-quality materials. Avoid albums constructed of highly colored pages. Never use commercially available “magnetic” or “no stick” albums for the storage of contemporary or historic photographic prints in black-and-white or color. These materials will deteriorate quite quickly over time.
However, in the digital age, you have some options for displaying treasured photo images that did not exist previously.
- Have your negatives and/or prints professionally scanned and stored on a DVD or CD. ScanCafe comes highly recommended.
- Have the digital images reproduced and printed as needed. You can reprint the images as many times as you’d like. SmugMug is one of many recommended providers.
- Create an online scrapbook to share with the world. Flickr is one of many such online services.
- Have a photo book of your photo album printed, and you can sell copies to friends and relatives. Blurb is one of many recommended providers.