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Microfilming Specifications and Inspection Guidelines

The objective of the U. S. Newspaper Program is to produce high-quality microfilm surrogates of newspapers that will satisfy the needs and requirements of researchers, archivists, librarians, and the general public for all reasonably anticipated purposes, including the use of both text and image material for general and scholarly research, as well as the use of newspaper images for display or exhibition purposes. Every effort shall be made to record in the new format all information contained in and issued with the original newspaper, and to maintain the integrity and authenticity of the representation of the original document on microfilm.

See other appropriate sections of this document for advice and guidelines regarding physical preparation of materials for filming, including disbinding and repair; collation, including bibliographic preparation and targeting; post-filming quality control and inspection; and additional advice and guidelines for reference when outsourcing preservation microfilming work. For all of the above, individual project approaches will vary widely, depending on the number and age of newspapers involved, the geographic area covered, the equipment and space available (if any) to organize and prepare the papers for filming, and the choice and location of the filming agency.

General Specifications

1. As the final product will be roll film to be used by the public in a broad range of microfilm readers, optimum legibility shall be the determining factor throughout the preparation and filming process. Image orientation and reduction ratios shall be selected with the objective both to fill the frame and to obtain the greatest possible degree of legibility in public use copies. The choice of image orientation shall be determined by the size of the pages, type size, and the number of pages per issue.

2. First generation microfilm of newspapers shall provide a high resolution quality to allow duplication through as many as four generations. In determining the reduction ratio, the quality index (Q.I.) Method as described in ANSI/AIIM MS23 - 1998 shall be used, with the understanding that other factors - most importantly the condition of the newspapers themselves - will directly influence the choice of both image orientation and reduction. For the master negative (first generation) a quality index of 8.0 or above is generally expected. Variation from this expectation, with specific information regarding how factors other than Quality Index will affect desired reduction and resolution, shall be communicated to the project and resolved prior to filming.

3. Filming shall be done on a planetary camera with variable pull-down. The camera shall be capable of high resolution. For example, when the e-height is 1.3mm, the camera system should be capable of resolving from 128 to 160 line pairs on the master negative depending upon the reduction ratio (generally 16X to 20X). Looking at this another way, the lowest allowable pattern resolved after looking at all 5 resolving power patterns on he technical target will be between 8.0 and 7.1, at a reduction ratio of between 16X and 20X.

4. Filming will generally be done on a black background. As the background and contrast of the pages to be filmed on the same reel changes, the camera operator shall adjust illumination or in some other way compensate to make the density of the negative images relatively even throughout the reel. Exceptionally, in order to adequately capture detail in photographs or other fine detail illustrations, or to capture important color variations, intentional duplicate exposures at variant illumination settings may be used. In those instances, informational targets shall be included to alert the reader of the duplicate exposure.

5. The institution and/or microfilming agency shall produce, in accordance with referenced standards and specifications, for each newspaper title:
• one set of silver negative first-generation preservation master microfilms, which shall be used only to produce:
• one set of second-generation silver negative intermediate print masters, from which will be produced:
• X number of positive service copies.

6. For the first-generation camera negative, only camera speed, panchromatic, extremely fine grain silver-gelatin type document recording film coated on a minimum 0.102mm (4 mil) unperforated polyester base with an anti-halation dye system as described in NAPM IT9.1 (latest version) and ANSI PH1.51 (latest version) shall be used. Only safety microfilm as defined by ANSI PH1.25 (latest version) shall be used.

6. For the second-generation intermediate print master, non-reversing silver-gelatin unperforated polyester-based duplicating film shall be used.

7. Only undamaged film stock with an unlapsed manufacturer’s expiration date shall be used. The film type, stock number and expiration date shall be recorded on the microfilming
agency’s identification target.

8. Silver halide microfilm must be developed only with an organic developing agent that is compounded to produce an essentially black image, fixed in a thiosulfate bath, and washed with water to remove residual hypo (sodium thiosulfate). Under no conditions should any use be made of developers that are intended to produce stained or colored images, or of any "hypo eliminators." The maximum permissible concentration of thiosulfate ion residue on the microfilm after processing will not be greater than 0.014 when determined by test results described in ANSI PH4.8 - 1985 (latest revision). See also NAPM IT 9.1 - 1996, Imaging Materials - Processed Silver-Gelatin Type Black and White Film, Specifications for Stability.

9. The microfilm development process shall be monitored at least daily using sensitometric control strips as described in MS23-1998 (section 6.1.6). Results shall be logged and the log shall be made available for consultation by a designated representative as required.

10. ISO Test Chart No. 2, (also called the Resolution Test Target throughout this document) arranged as specified in ANSI/AIIM MS111 - 1994, shall be filmed immediately preceding the unit target and text portion of each reel and immediately following the text portion of each reel. Only clean, flat, certified targets are to be used. No photocopies or unauthorized reproductions of targets are to be used. To insure that the resolution test target is filmed on the same camera, at the same time, and under conditions that will achieve the same background density as the text, there shall be no splices between the resolution target and the adjacent ten frames of text, both at the beginning and at the end of the reel.

11. Processed film shall meet the requirements of NAPM IT9.1 - 1996 (or latest version).

12. Processed film shall be inspected as soon as possible after processing is completed. Inspection records shall be maintained and made available for review.

13. Clean film inspection gloves shall be used at all times when handling film.

14. Methylene blue tests to detect residual thiosulfate shall be conducted whenever chemicals are changed and no less than once weekly. If more than five reels of film are being processed per day, daily testing is required. If any test shows that the level of residual thiosulfate is unacceptable according to ANSI/NAPM IT9.17 (latest version), all film processed since the last preceding test shall be re-washed and inspected. If methylene blue testing is being done offsite, copies of certification and test results shall be maintained and provided upon request.

15. Each reel of first generation film shall be inspected throughout for visual transfuse density, and no less than five density readings per roll shall be taken with a transmission densitometer. Densitometers must be calibrated daily according to the manufacturer’s specifications. Readings shall be taken at the beginning, middle and end of each reel. Maximum (Dmax) density measurements shall be taken on a portion of the exposed image in which in which there are no words or graphics. (With filmed images of newspapers, it is often necessary to take readings in advertising spaces because outer margins are commonly darkened, yellowed, or faded and there are no other areas large enough to take readings where text appears.) Sets of readings from identical pages and spaces within pages should be compared if results are questionable or vary widely from those reported by the filming agency.

16. Background densities on the camera negative shall be no lower than .80 and no higher than 1.20, with an aim point of 1.0 for newspapers of average text quality. Lower densities are preferred for older pages that are uniformly browned or yellowed. Where practical, lower density ranges are preferred over higher to facilitate the production of reader-printer and enlargement prints. Base-plus-fog density (Dmin) on the master negative shall not exceed .10. A permanent record of results shall be maintained to allow detection of any changes on future inspection.

17. To verify Quality Index Value (see ANSI/AIIM MS23-1998), all five resolution test charts (see 10.) shall be read with the aid of a 100X microscope. A permanent record of results shall be maintained to allow detection of any changes during future inspections.

18. Each roll of first generation film shall be inspected frame-by-frame by both the filming agency and the project for density and resolution and to determine that the film is free of emulsion scratches, abrasions, fingerprints, spots, fog, and other defects listed in ANSI/AIIM MS23 - 1998. No inspection equipment or procedure shall be used that might scratch or damage the film.

19. Each roll of first generation film shall be inspected frame-by-frame by both the filing agency and the project to determine whether all bibliographic requirements have been met and whether all pages have been filmed and appear in proper sequence. No inspection equipment of procedure shall be used that might scratch or damage the film.

20. Each roll of second generation (print negative) film shall likewise be checked for resolution and density. A drop in density of more than one point (.01) from master negative to print negative is unacceptable. A drop of more than one resolution pattern read from the master negative to the print negative is unacceptable.

21. If there is a discrepancy between the film product and the collation sheets, the original newspaper file is the final source for determining if pages or issues have not been included on the film. All pages or issues provided by the preparer but omitted from the microfilm product shall be filmed and spliced into the master negative. Missing material shall be processed and inspected according to the standards and practices required for master negatives. Background densities shall vary not more than 0.10 from the master negatives into which they are spliced. If the number of permissible splices is exceeded (see below), the entire reel shall be refilmed.

22. All pages or images that are filmed improperly shall be re-filmed. Retakes shall be processed and inspected according to the standards and practices required for the master negative. The background densities of retakes shall vary not more than 0.10 from other images on the master negatives into which they are to be spliced. Retakes due to improper filming shall be spliced into the master negative in the sequence(s) in which the material appears in the original newspapers, not at the beginning or ends of reel. Under no circumstances are splices to be placed between the technical targets and the text.

22. The number of splices on a given reel shall not exceed four spliced segments (8 splices). If more than 8 splices are required, the entire reel shall be refilmed.

23. When filming retakes to be spliced into the master negative, additional pages or blank frames preceding and following the retake shall be included to avoid defacing images when splicing and to compensate for any density fluctuation that may occur in images near the splice while the film is being duplicated.

24. Splices shall only be made on the camera master negative. All splices shall be made with an ultrasonic splicer. The splice may be smooth or serrated in appearance (the serrated splice is presumed to be more durable), but no portion of the splice shall protrude beyond the edge of the film. No splices shall be made on print negatives or service copies.

25. Pages or issues missing from the file when the camera master negative is produced may be discovered at a later time. Whether the pages are filmed and spliced into the original masters or the entire newspaper file is refilmed is to be determined on a case-by-case basis. Bibliographic and holdings data, including targets and box labels when appropriate, shall be amended to reflect the more complete version of the microfilm.

26.. Film storage enclosures shall meet the requirements of PIMA (paper) IT9.2.

27. Microfilm shall be wound per instructions and referenced standards in ANSI/AIIM MS23 on non-corroding inert plastic reels as specified in ANSI/AIIM MS34.

28. Microfilm shall be boxed in long term storage containers in compliance with PIMA (paper) IT9.2. Labels and fastener strips shall be in compliance with PIMA (paper) IT9.2. Rubber bands shall not be used to secure film on reels. Pressure sensitive tape shall not be used.

29. Master negative film shall be stored in compliance with the extended term storage specifications and the referenced standards for air conditioning, fire resistance and control, and environmental conditions in ANSI/NAPM IT9.11. The storage area shall be fire-resistant and free of impurities that might damage the film.

30. For extended term storage purposes, it is preferred that first generation film be stored in a high-security vault physically separate from the storage site used for second generation film.

31. Second generation (print) negative film shall be stored as indicated for first generation film in item 29, above.

Notes on Microfilm Quality Control

It is generally considered acceptable practice that complete technical and frame-by-frame inspection as described in ANSI/AIIM MS23 shall be performed on the first 100 reels of film, whether created by an in-house camera technician or by a contracted microfilming agent. As camera work reliability is demonstrated, technical inspection (light box inspection to detect defects, check splicing, take resolution readings and check density) may be reduced to every tenth reel. If the microfilming agency has factored inspection into the microfilming cost, obvious defects and errors shall detected at the point of filming and corrected before the film is shipped.

Bibliographic concerns are another matter. It is imperative that every effort be made to check one copy of the film (preferably a service copy) frame-by-frame to make sure all of the material has been filmed, and filmed in the correct order. It should be required to do so if the film has been created using the only existing copies of the paper, particularly if those copies are not going to be retained. See also the RLG Preservation Microfilming Handbook (1992), Appendix 18.

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  August 5, 2010
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