By MARK ROOSA
Some important but less well known images of Ansel Adams will soon be available online, thanks to work of the Conservation Division.
Each year, staff in the division work closely with Library curators to select items and collections for treatment. Their discussions produce a list of projects that book, photograph and paper conservators will work on for the next 12 months. The lists contain some new projects and some continuing projects. And, once in a while, there are some surprises. Such was the case several years ago when Prints and Photographs (P&P) Division curators placed on their "top priority" list a collection of photographs by Ansel Adams, the famous American landscape photographer. While most are familiar with Adams's lush black-and-white landscapes, most of the public is not familiar with his other work, such as this group of photographs that documents life in the Japanese internment camps during World War II.
While the subject matter is unusual for Adams, the materials used for the project are typical of his work. The photographs are silver gelatin prints. Adams treated most of them with selenium, giving them a characteristic slightly dark-blue tone. Selenium also helps to increase their longevity. After processing, Adams dry-mounted the photographs directly to four-ply mat board. P&P curators had earmarked these images for treatment for two reasons: they were extremely fragile and there was concern that many were separating from their mounting boards. Thus, they could not be handled, used for research or exhibited.
The edges of the dry-mounted photographs are vulnerable to chipping and flaking, because these areas are raised slightly above the surface of the mount board. Over the years, tiny areas of the image have become detached along the edges. All photographs were examined under a microscope to determine the extent of edge chipping. Detached areas were reattached using a dilute solution of photographic grade gelatin and a very small brush. Some photographs had separated from their mounts. These were reattached with Japanese paper and wheat starch paste. The conserved photographs were then housed in mats to protect the edges from damage in the future. Testing was conducted on the mat board to ensure that it passed the Photographic Activity Test, a national standard that determines whether housing materials are safe to use with photographs.
Because there are significant differences between the negatives and the enhanced photographic prints Adams produced, the full set of both the negatives and prints will be digitized. (For those interested in the technical aspect of the digitization: The negatives were captured as 12-bit grayscale images [7,000-10,000 pixel TIFF] and the prints as 36-bit color images [7,000-10,000 pixel TIFF]. Those raw digital files were then processed and saved at a higher bit depth to create master files of 16-bit grayscale for the negatives and 48-bit color for the prints, in order to capture Adams's distinctive toning. These higher-quality files have a more precise brightness and contrast correction and, therefore, better reflect the subtleties of the originals.)
When the digitizing is complete this fall, background essays about the project and links to the digital reproductions will be available on the Preservation Digital Reformatting Program Web page (www.loc.gov/preserv/prd/presdig/presintro.html).
Mr. Roosa is chief of the Conservation Division. Andrew Robb, senior photograph conservator, and Lee Ellen Friedland, senior digital conversion specialist, assisted with this report.