LOC Facility Copes With Plethora of Formats

Technologies for capturing and storing sounds and moving images first came into being more than 100 years ago and have been constantly evolving. This makes the jobs of Library of Congress audio visual archivists and preservationists both interesting and challenging.
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Technologies for capturing and storing sounds and moving images first came into being more than 100 years ago and have been constantly evolving. This makes the jobs of Library of Congress audio visual archivists and preservationists both interesting and challenging.

Technologies for capturing and storing sounds and moving images first came into being more than 100 years ago and have been constantly evolving. This makes the jobs of Library of Congress audio/visual archivists and preservationists both interesting and challenging. While it is relatively easy to extract content from a 35mm motion picture footage or a Betacam SP cassette, this not true for many other materials at the Culpepper, Va., facility.

Part 2 of 2
Part 1, “Digitizing History,” appeared in the December 2009 Government Video.

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One of 14 special turntables for playing back disk recordings, on a heavy stone base and isolated from vibration by an air bag. PHOTO: JAMES E. O'NEAL by James E. O'Neal


Thomas Edison made his first audio recordings in 1877 and later turned this technology into a commercial product. His company captured a very wide variety of audio and marketed its recordings primarily in the form of wax cylinders with vertically modulated grooves.

The company finally exited the recording business in 1929, but not before it produced an extremely large number of recordings. While many Edison cylinder recordings still exist in fairly good condition, the same cannot be said about the devices for playing them, with the reproducers that do turn up usually not being functional. To complicate matters, the cylinder recording industry used recording speeds that ranged between 90 and 180 rpm. Groove pitch and depth varied also, along with the diameter of the cylinder.

The LOC plays back its cylinder recordings with a machine that would have been unavailable even to the extremely wealthy during the heyday of the Edison technology-the Archeophone cylinder reproducer. It’s driven, not by a clockwork mechanism, as was standard on most Edison machines, but rather by a microprocessor-controlled electric motor. The device can reproduce virtually any cylinder format with fidelity undreamed of a century or so ago.

An equally sophisticated technology for recovering content from slightly more modern recording media-phonograph discs-is also part of the LOC’s tool set. This is a very high-tech turntable crafted on a limited basis by Simon Yorke Designs.

Only a very small number of these specialized turntables have been produced and the LOC has 14 of them. They allow fine tuning of platter speed from 78 rpm down to 1/100 of an rpm and are constructed on a high-density slate base for stability. The entire turntable rests on an air bladder, which provides isolation for building noises or other vibrations that might interfere with the best possible reproduction of a phonograph recording.

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Playing back EIAJ half-inch open reel video recordings is part of a day’s work at the Library of Congress Culpepper facility. Machines such as these make it possible. PHOTO: JAMES E. O'NEAL These turntables are used with special preamps equipped with equalization pre-sets for all known recording curves, and also allow users to dial in a custom EQ to accommodate any oddball recordings that might be encountered.


Recovering images and sound from motion picture footage is somewhat easier for archivists, as 16mm and 35mm formats were standardized by most movie production companies decades ago. And while telecine equipment of one sort or another has been available for this task since the dawn of broadcast television, the LOC relies on a state-ofthe- art DataCine device, which not only provides film to tape transfers, but is also capable of creating 2K high-resolution digital images.

More arcane film formats do exist and the Library is also equipped to deal with most of these. One of the more interesting resembles standard 35mm motion picture footage, but began arriving at the LOC more than 100 years ago on paper, rather than conventional film stock.

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Although the motion picture companies stopped sending paperbased prints to the LOC in 1912, The need to recover images from them still exists. Migration to conventional film stock is made easier with this special scanner. PHOTO: JAMES E. O'NEAL As U.S. copyright laws predated the motion picture industry, celluloid film was not a recognized medium for submission of works to be copyrighted. This required early film makers to pull positive paper prints from their negatives. Laws were updated in 1912, reflecting the growth of the cinema industry and recognizing motion picture film stock as suitable medium for copyright, but not before the Library had amassed a large number of paper prints. Years ago, these images had to be printed frame-by-frame onto film stock in order to be viewed as a motion picture. This process changed with the advent of specialized equipment that is able to rapidly convert these streams of paperbased images into a motion picture format. A special scanner generates digital files that can be cleaned up or otherwise restored, and the resulting files are then transferred back to motion picture stock via a film recorder. Even though the recovery and transfer process is somewhat involved, these paper positives have proven to be a blessing in disguise, as in some cases the 35mm nitrate stock from which they were printed has decomposed to the point that the paper imagery provides the best-or in some cases the only-version of some early motion pictures.


During the last few decades, videotape recording has replaced film in many applications. While in theory, recovering magnetically stored images should present no real challenge, due to the numerous and rapid developments in video recording technology since its introduction in 1956, the playback of some videotapes is complicated due to the very large number of recording formats developed. Also, support for many video tape formats-in terms of machine and parts availability, as well as personnel with necessary maintenance skills to keep the VTRs running-is waning, especially since the shift to a “tapeless” television environment.

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The Art Deco theatre is one of the few theatres today equipped to project potentially dangerous nitrate-based film. PHOTO COURTESY COMMUNICATIONS ENGINEERING INC. (CEI) However, the Library has secured a substantial number of video recorders in various formats and embarked on a long-term program to migrate content to digital storage while it can still be recovered.

An offshoot to this videotape migration program was the development of automated or robotic machines for coping with the massive amount of videotape accumulated by the LOC. These devices are known as SAMMA robots and were developed by Jim Lindner, an expert in the field of A/V preservation and founder of SAMMA Systems (acquired in 2008 by Front Porch Digital).

The machines were designed expressly for high-volume automated migration of cassette tape content at the LOC and other organizations with huge video libraries. The robots automatically perform inspection and cleaning operations, issue a “pass/fail” flag for individual cassettes, and then play and digitally encode the recording if everything passes muster. Each of the robotic units can accommodate either 48 U-Matic tapes or 60 Betacam cassettes and they’re content to work on a 24/7 schedule, requiring human intervention only for unloading processed cassettes, loading in new ones and some occasional maintenance. The collection size at the LOC is so vast, even with multiple SAMMA robots working round the clock; it will still take years to migrate everything to digital storage.


While its primary mission is stewardship and conservation of the nation’s audiovisual treasures, the Culpeper facility is more than an extremely large media library and workplace for those involved in preserving the great audio/visual past. It has other functions too.

One of these is the public display of some of the facility’s content. A specially designed 200-seat replica of a 1930s Art Deco motion picture theater is also part of the Culpeper campus. It’s authentic down to lighting fixtures and specially woven carpet pattern. A specially constructed electronic organ was also included in the design, and was styled to replicate its piped ancestors, with the console rising out of the stage depths on an elevator-controlled pedestal.

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The theater was designed to accommodate 16mm, 35mm, 70mm optical prints, as well as digital cinema offerings. The projection booth is one of an extremely small number that can safely handle nitrate-based prints. This capability allows the side-by-side screening of an original nitrate print with a fully restored safety film base or even a digital cinema version.

The theater is opened to the public on a regular basis, with free screenings of classic films from the library’s collection.

James O’Neal is the technology editor of TV Technology magazine.