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Microfilming: Quality assurance

OCLC Preservation Service Centers are dedicated to maintaining the highest quality at every step in every service we provide. Our quality assurance staff confirms that film meets all preservation microfilming specifications and that all information from the original material is completely and accurately captured and preserved. Each generation of film undergoes a rigorous inspection procedure to ensure that every frame filmed is of the highest quality.

Below is an overview of our QA process, from Archive Master through Print Master to Service Copies:

  • Archive master
    After an archive master is processed, our quality assurance staff inspects the film and records resolution readings and densities to ensure compliance with preservation standards. Images with densities or resolution readings outside preservation guidelines are refilmed. The archive master is then inspected frame by frame to look for bibliographic or technical problems, and retakes are issued for any frames requiring refilming. Pertinent information is recorded on an inspection form that accompanies the reel when returned to the client. After the inspection, a supervisor reviews the reel and completed inspection form before the reel is duplicated. The archive master should be duplicated once to produce a print master, and then stored in a climate-controlled vault apart from the print master. Once in storage, the archive master should be used only to create another print master, should the original print master be damaged or lost.
  • Print master
    A second-generation direct duplicate is made from each archival master, using Kodak 2470 or 2468 film. This print master is inspected for appropriate densities, resolution, and other quality measurements, such as legibility of all images, and freedom from scratches. It is then used to create third-generation positive service copies.
  • Service copy
    A third-generation positive service copy, intended for use by researchers, is created from the print master. Following duplication onto Kodak 2462 film, the service copy is inspected for appropriate density, resolution, and other quality measures.
  • Final 10% check
    Ten percent of reels from every shipment are put on a non-scratching microfilm reader again and given an additional frame-by-frame inspection. Reel selection for the 10% service copy check is designed to include material filmed by each camera and camera technician, providing additional quality assurance for our clients.