Saturday, January 18, 2014

Preserving the photographic record


        The Library of Congress and the National Archives among other organizations have great information on line about the preservation of photographs both digital and physical.  I’m going to add my two cents, but I urge you to check out the web pages listed below.  They will provide answers to all of your questions.

        Success in preserving photographs depends on two factors: (1) the stability of the original materials used – the film, processing, and print paper – and (2) storage conditions.  Black and white negatives and photographs are very stable and will last a long time, over a hundred years if cared for properly. Color slides are also very stable (10-50 years).  Newer color images using 1990s processing and films are more stable then they were in the past, but still will fade over time.  The best book on the preservation of photographs is by Henry Wilhelm and Carol Brower and is entitled The Permanence and Care of Color Photographs.  A free pdf of the book is available at http://wilhelm-research.com/book_toc.html.  Check it out.  They tested color films and processing and discuss the preservation problems of primarily color photographs.

        Most black and white photographs will be in better condition than any of your older color ones regardless of the care you have given them.  Most of the processes, film and papers used particularly in the fifties, sixties, and seventies for color photographs, were inherently unstable.  Pictures have yellow staining or purplish (magenta tones), and some are blue.  None of this fading and discoloration is your fault.  Blame it on Kodak Ektachrome film and RC (non-fiber papers).  Professional photographs taken during the period are often the most deteriorated.  It wasn’t the photographer’s fault.  It was the products he or she used.  There’s not much that you can do.  My recommendation is to scan the pictures you like and if you want to balance the color use Photoshop software.

          Generally photographs should be kept in the dark, in cool, dry places.  Placing the material (negatives, slides, or prints) in inert sleeves will protect them from improper handling and will keep them from sticking together if there is any moisture between them.  At Texas Tech we used refrigeration units (fancy refreigerators and freezers) set below freezing to preserve slides and negatives.  Before using any we would slowly allow the material to warm to room temperature over several hours.  With the advent of scanning technology favorite negatives and slides can be digitized to provide another avenue of preservation.  I wouldn’t throw away the original because the longevity of digital materials as we said before is so dependent on rapidly changing technology so who knows how long that photograph will be accessible. If you want to display a photograph, make a copy and keep the original in proper storage.  Photographs should be matted using acid-free mat board.  Never should a photograph directly touch glass.  If there is any moisture, it could stick.  UV filtered glass is best.  Costs a little more though.  Display the photograph away from direct sunlight and ideally rest it every so often by not displaying it for awhile.

        Don’t forget to label your material.  For photographs, as I said, use either graphite pencil, a No.2 pencil, or a special India ink pen.  Be careful ink and the graphite pencil can smudge especially on RC paper prints.  Slides can be labeled on the slide cover.  Negatives can be marked with the India ink marking pen on the chemically inert sleeves. Some museums will not mark directly on the back of the picture, but instead label the sleeve or housing folder.  A label insures that your descendents know about the people in the photograph. 

There are lots and lots of web pages about photographs.  Here are a few. 
http://www.archives.gov/preservation/family-archives/captioning-photos.html (labeling photographs. Says what I said only better)

No comments:

Post a Comment