Records Management Standards and Guidelines
- Contents
- 1.0 Purpose
- 2.0 Authority
- 3.0 Permanent Records
- 4.0 Standards for Microfilming Records
- 5.0 Microfilm Base
- 6.0 Processing Film
- 7.0 Criteria for Using Microfilm Copies of Public Records
- 8.0 Guidelines for Handling and Inspecting Microfilm
- 9.0 Guidelines for Storing Microfilm Copies of Permanent Records
- 10.0 Deteriorating Film
- A. Sources of Additional Information
- B. Glossary
This manual is to assist records custodians in complying with microfilm standards approved by the Board of the Library of Virginia in accordance with the provisions of Chapter 7, Virginia Public Records Act, Section 42.1-82 of the Code of Virginia. It is to ensure the creation and preservation of acceptable permanent microfilm copies of records scheduled for permanent retention or to substitute for non-permanent records that are being filmed on planetary and rotary cameras and the originals will be destroyed after filming. Beside the basic information in producing acceptable microfilm, there is a list of suggested filming target sequences for roll microfilm and terminology located as an appendix. Those needing further assistance should contact the:
- The Library of Virginia
- Archives and Records Management Services Division
- 800 E. Broad Street
- Richmond, Virginia 23219
- Telephone: 804/692-3600 or 804/236-3705
Responsibility for preserving the permanently valuable public records of state and local government is vested with the Library Board of the Library of Virginia in accordance with the provisions of Chapter 7, Virginia Public Records Act, Section 42.1-82 of the Code of Virginia. All public records that have been appraised as being permanent have administrative, legal, fiscal, or historical value as defined in Section 42.1-77of the Code of Virginia to warrant their continued preservation. Such determinations are included in the officially approved retention and disposition schedules. When the informational contents of such are to be maintained on microfilm, the camera negative produced by source document methods is to be considered the permanent backup to the original, and the silver negative should be sent to the LVA for permanent retention. Computer-Output-Microfilm (COM) records are generated directly from computer files and are not part of this guideline.
Permanent records are any records determined by the appropriate record retention and disposition schedule to have sufficient value to warrant their continued preservation.
4.0 STANDARDS FOR MICROFILMING RECORDS
Agencies microfilming permanent and vital public records must comply with the following standards approved by the American National Standards Institute (ANSI), Association for Information and Image Management (AIIM, International Standards Organization (ISO) and State standards. They relate to the microfilm, microfilming, film processing, and film storage of public records.
ANSI
IT 9.1 - 1992 Imaging Media (Film) - Silver-Gelatin Type - Specifications for Stability
IT 9.2 - 1991 Imaging Media - Photographic Processed Films, Plates, and Papers - Filing Enclosures and Storage Containers
IT 9.17 - 1993 Photography - Determination of Residual Thiosulfate and Other Related Chemicals Processed Photographic Materials - Methods Using Iodine-Amylose, Methylene Blue and Silver Sulfide
IT 9.11 - 1993 Imaging Media - Processed Safety Photographic Film Storage
PH2.19 - 1986 Conditions for Diffuse and Doubly Diffuse Transmission Measurements
ANSI/AIIM:
MS08 - 1988 Image Mark (Blip) Used in Image Mark Retrieval Systems
MS14 - 1988 Specifications for 16 and 35 Microfilms in Roll Form
MS18 - 1992 Splices for Imaged Film - Dimensions and Operational Constraints
MS19 - 1993 Recommended Practice for Identification of Microforms
MS23 - 1997 Practice for Operational Procedures/Inspection and Quality Control of First Generation Silver Gelatin Microfilm of Documents
MS42 - 1999 Recommended Practice for the Expungement, Deletion, Correction or Amendment of Records on Microforms
MS45 - 1990 Recommended Practice for Inspection of Stored Silver Gelatin Microforms for Evidence of Deterioration
TR02 - 1992 Glossary of Imaging Technology
Other:
ISO 3334 - 1989 Microcopying: ISO Test Chart No. 2: Description and Use in Photographic Documentary Reproduction
Y14.2M - 1987 Engineering Drawing and Related Documentation Practices - Line Conventions and Lettering
4.1 General
The integrity of the original records authorized for microfilming should be maintained by ensuring that the microfilm copies are adequate substitutes for the original records and serve the purposes for which such records were created and/or maintained. All of the following measures, and any others found necessary, should be observed in any microfilming project that is designed to ensure the preservation and integrity of the records filmed on a planetary or rotary camera.
4.1.1 Document Preparation and Filming
- All staples, paperclips, pins and attachments must be carefully removed prior to document filming. When using a rotary camera, attachments and documents that are smaller than 3" x 5" should be removed and taped to an 8.5x11" piece of white.
- Only when using a rotary camera are tattered or torn documents to be mended to eliminate camera malfunction, filming errors and to protect the original public records against further damage. This does not apply to valuable historical documents. These should be mended only with the advice from a professional conservator. Please contact Archives and Information Services at 804 692-3556 for assistance in evaluating your documents.
- To eliminate creases or fold in documents, they should be flattened or taped with transparent tape to eliminate shadows, risk of damage to the document or camera malfunction. Do not use tape on valuable historical documents.
- Documents should be arranged and filmed in a manner consistent with their customary reference and usage unless specified by the record custodian.
- Pages located in a notebook binder should be removed for filming provided that they may be replaced without damaging the book. Sewn books must be filmed in such a manner so as not to break or destroy the binding. For additional instructions, please contact Imaging Services at the Library of Virginia at 804 692-3607.
- Images located on roll film, including the user's copy, should contain all of the significant record detail shown on the originals.
- The film images of the records should be arranged, identified and indexed so that any individual document or component of the records can be easily located.
4.1.2 Density and Resolution Requirements
Photographic densities should be as consistent as possible throughout the microform. The background density of the camera negative microfilm should be within the ranges shown on the following chart when measured on a blank area of the filmed document.
- Classification Description of Document
- Group 1 - - Density 1.00 - 1.20
- High quality, high contrast documents or printed material and black typing; fine line originals, black opaque pencil small high-contrast printing; Pencil and ink drawings, faded printing and very small printing.
- Group 2 - - Density .80 - 1.00
- Low-contrast manuscripts and drawings graph paper with pale, fine-colored lines; letters typed with a worn ribbon; poorly printed, faint documents; positive appearing Photostats and blueprints.
- In certain instances, some poor-contrast documents may require lower densities to make the entire image legible and reproducible as mentioned an ANSI/MS23-1997, and others may require a higher density. Mixed quality documents should be filmed at the lower densities.
- Background density on positive appearing camera microfilm should be no higher than 0.35. The base-plus-fog density of unexposed, processed, clear-based film must not exceed 0.10. For Computer Output Microfilm (COM), refer to Standards For Computer - Output Microfilm (COM) For Public Records. See section 8.0 of this guideline on steps to handle and inspect microfilm.
- A minimum resolution of 90 lines per millimeter must be obtained regardless of reduction ratio used or the type of camera used and the 4.0 pattern must be resolved for public records. For procedural microfilm recording, a minimum resolution of 120 lines per millimeter must be obtained regardless of reduction ratio used or the type of camera used and the 5.0 pattern must be resolved for 16mm microfilm. For 35mm, 6.3 pattern is required. A 3.2 pattern for 16mm microfilm generated from using recorded digital images must be obtained.
- The National Bureau of Standards Standard Reference material 1010a (ANSI and ISO Test Chart No.2) for planetary cameras and the AIIM MS-113 Test Chart for rotary cameras should be filmed at the beginning and at the end of each reel of camera microfilm at least three times in succession. No other test charts are to be used unless approved by the Library of Virginia.
- Each test chart is composed of two groups of fine lines pairs, with the line pairs in the two groups being oriented perpendicular to one another. Each pattern is numbered and progressively reduced. Five vertical and five horizontal line should be clearly defined in both directions.
- Resolution of duplicate film copies should only be one pattern lower than the original from which the duplicate was reproduced.
4.3 ROLL MICROFILM
4.3.1 Photographic image targets should provide documentation that ensures the microfilm copy can be substituted in place of the original document. The film targets should include the following: 1) start target, 2) reel number, 3) resolution chart (filmed three times), 4) plain white sheet of paper, 5) Title page, 6) custodian's certificate, 7) End of Records or Volume, 8) operator's declaration, 9) End of Reel or Continued on Reel #, 10) resolution target (filmed three times), white paper and 11) rewind target. Any other technical targets as needed.
4.3.2 The titling target must identify the agency or locality and subordinate organizational unit(s) whose records it covers; the title of the records (with identification of contents if not evident from series title); the inclusive dates; volume numbers or file numbers; the data identifying the first and last records on the roll; and the producer of the film. MS23 and MS19 list additional technical targets. Also see LVA's Microfilm Storage Guidelines.
4.3.3. Any index, registers, or other finding aids should be microfilmed at the beginning of the records to which they relate. If the index is located at the end of the volume and unnumbered, it should be microfilmed at the beginning of the record. If the index is numbered, it should be filmed in the order of sequential appearance. This is especially true if an automated retrieval system is currently or will be used in the office.
4.4 OTHER MICROFORMS (Aperture Cards, Microfiche and Jacketed Film
4.4.1 The system should be designed and administered in a manner to reflect the microfilm file in an accurate representation of the original records.
4.4.2 Any indexes, registers, or other find aids should be microfilmed and located in a readily identifiable place within the collection of microfilmed records.
4.4.3 Individual microfiche must be identified in the header of each fiche. This should include the name of the agency or locality, the title of the records, date ranges, beginning file and last file number of each individual one.
4.5 MICROFORM HEADINGS
The data on head or title areas on all microforms shall be legible with at least 8X magnification. See LVA's Guidelines and ANSI/AIIM MS19-1993 Recommended Practice for Identification of Microforms.
5.1 The film stock used to make permanent archival security photographic or microphotographic copies of public records should be safety-base archival microfilm as specified in IT9.1 - 1992 Imaging Media (Film) Silver-Gelatin Type Specifications for Stability.
5.2. To provide adequate protection for permanent records, agencies using microfilm systems that do not produce an camera negative which meets the standards for public records must make a silver gelatin duplicate negative or silver gelatin master positive which does meet the standard.
6.1 The silver gelatin exposed polyester film must be processed properly as required by the processor's manufacturer. This should produce an archival quality processed film as required by IT 9.17 - 1993 Photography - Determination of Residual Thiosulfate and Other Related Chemicals I Processed Photographic Materials - Methods Using Iodine-Amylose, Methylene Blue and Silver Sulfide.
6.2 The polyester film used to make photographic or microphotographic copies of the public records should be processed in order to perform the methylene blue test. This test measures the amount of residual thiosulfate ions left on the processed film. It should not exceed 0.14 g/m in a clear area. However, this is different for fine-grain archival films. See ANSI 9.1 - 1992 for this setting.
6.3 Film processed in-house should be tested and certified once every two weeks or as deemed necessary by Microfilm and Optical Imaging Services at the Library of Virginia. Processing services performed off-site should be included in the provisions requiring that the methylene blue test be performed every 24 hours. It documents the testing. Please contact the Imaging Services for details.
6.4 The documentation must be maintained. It contains the name of the agency whose film was processed, the date of processing, the date the methylene blue test was performed, the test results, processor used and the signature of the person who did the tests.
6.5 A certificate documenting that the microfilm passes the methylene blue test must be sent to the Imaging Services of the Library of Virginia at least once a month.
7.0 CRITERIA FOR USING MICROFILM COPIES OF PUBLIC RECORDS
- The following criteria are required in using microfilm copies of public records:
-
- (a) the original camera film (master) of records created for permanent retention should never be used for reference purposes. An intermediate silver master should be created and used to produce additional user's copies. The user's copies may be either silver or diazo depending upon the quality of the original documents and camera negative film.
- (b) Adequate measures shall be taken to keep microfilm clean and minimize the amount of scratches during any inspection and duplication process. Care shall be used when handling any silver copies of any microfilm.
8.0. GUIDELINES FOR HANDLING AND INSPECTING MICROFILM
The total microfilming system should be evaluated to ensure that the micro-images produced conform to the standards. The final reproduction, whether film or photoprint from the film, must be retrievable, readable and reproducible. The following criteria are required in handling and inspecting the microfilm:
- Clean, lint-free, white cotton or nylon gloves should be worn when handling the film. The microfilm should also be handled by the edges.
- Food, smoking and other contaminants should not be allowed in the microfilm production and quality control areas.
- The camera microfilm should be handled only during the inspection procedure, editing stage, and when generating an intermediate master. In systems generating two rolls of camera negative simultaneously, one should be designated as the archival camera microfilm. As designated "archival" film, it should not be used for duplication, loaded into a cartridge or inserted in a reader or reader/printer.
- In systems generating a single camera microfilm, the roll of film should be used only for the production of an intermediate master.
- Splicing is not permitted with certain exceptions. The images are to be spliced at the beginning of the reel before all beginning targets but after the clear leader. For procedural recording or other coding methods, splicing can be done in place on the intermediate master up to a total of five splices. An unexposed area of film must be used between the splice and the beginning title targets. Ultrasonic splicing is recommended for polyester film. The splicing should be done so that it does not impair the integrity of images nor interfere with blip or other code methods. There should be 24" leader of clear film for each roll of film
- Due to the required filming procedures, more than five splices within a single 16mm reel are permitted for procedural microfilming. However, each days filming sequence should be discarded and refilmed when defects obliterating or obscuring information or missing pages are noted within that sequence.
- The following equipment and supplies should be purchased to maintain a quality control program:
- Item - - Estimated Price
- Densitometer - - $1,500 - 3,000
- Microscope (minimum resolving power 100x) - - $450 - 1,200
- Eye loupe - - $8 - 20
- Light box with rewinds - - $600 - 3,000
- Inspection gloves - - $20 - 35 per dozen
- Resolution targets - - $30 - 75 per chart
9.0 GUIDELINES FOR STORING MICROFILM COPIES OF PERMANENT RECORDS
This section lists the requirements for storing silver gelatin original (master) microfilm copies or silver gelatin duplicate negative or silver gelatin master positive copies of permanent records. They should comply with ANSI/AIIM MS29 - 1992 Cores and Spools for Recording Equipment - Dimensions, ANSI/AIIM MS45 - 1990 Recommended Practice for Inspection of Stored Silver Gelatin Microforms for Evidence of Deterioration and IT 9.2 - 1991 Imaging Media - Photographic Processed Films, Plates, and Papers - Filing Enclosures and Storage Containers and LVA's Microfilm Storage Guidelines, Microfiche or Optical Media for Security Storage at the Library of Virginia.
Camera negative should be verified for completeness and accuracy, then transferred promptly to Imaging Services for storage as required in the appropriate Retention and Disposition Schedule. Each roll of film should be labeled with the following: office of origin, records series, reel number, inclusive information, producer, date filmed, density and resolution readings.
9.1 REEL AND CORES
Microfilm stored in roll form shall be wound on cores or on reels of the type specified in ANSI Standard Dimensions for 100 Foot Reels for Processed 16mm and 35mm Microfilm, ANSI/AIIM MS29 - 1992 Cores and Spools for Recording Equipment - Dimensions. The materials used for the cores and reels should be plastic compounds that do not give off reactive fumes or emissions during storage. Paper strips or rubber bands must not be used to fasten film onto reels or cores. The materials used should not ignite, decompose, or develop reactive fumes or vapors.
9.2 STORAGE CONTAINERS
9.2.1 Rolls of photographic film should be stored in a acid/lignin free film boxes to provide protection against dirt and physical damage. The acid/lignin free box shall contain buffer with less than 3% calcium carbonate.
9.2.2 Proper temperature and humidity should be maintained with good ventilation and clean air in the storage area. Films of different generic type (for example, diazo and silver gelatin) should not be stored together because of possible chemical reactions. Film of different generic types should not be wound on the same roll or stored in the same area.
9.2.3 The size and placement of the film box label and printed information should be consistent with the container. The surface of the label should readily accept writing with an ink pen, a common graphic pencil, or the addition of a sticker. The label should include the following minimum information: name of agency/locality, record series, dates of the records series, volume numbers, file numbers, reel number and producer.
9.3 STORAGE ROOM
It is recommended that original microfilm of public records be stored in a fire resistant vault, room, or storage facility. This storage must not be used as an office or working area. No flammable material or chemicals shall be stored in this area. For full protection against fire and its associated hazards, fire-resistant safes or insulated containers should be placed within fire-resistant vaults or rooms constructed in accordance with recommendation of the National Fire Protection Association. The LVA's Imaging Services Branch offers free archival storage of vital and permanent film records at the Vital Records vault. There is no charge for this service but the film must comply with the guidelines for storage. See Appendix for microforms to be accepted for storage.
9.4 ENVIRONMENTAL CONDITIONS
The relative humidity of the storage area must not exceed 40 percent. Temperatures must not exceed 70 F (21 C). Rapid and wide range cycling of humidity or temperature should be avoided and should not exceed 5 percent relative humidity or 5 F in a 24-hour period. Where inactivity of the film permits, protection may be increased by conditioning and sealing the film at a lower humidity and/or storing the film at a lower temperature. Film stored at a relative humidity below 30 percent or a temperature lower than 60 F (16 C) should be sufficiently warmed and conditioned before use to avoid any possible damage. If possible, approximately 0.05 inches of pressure above atmospheric pressure should be maintained in the room or vault and in the film inspection area by means of an independent air-conditioning system.
9.5 CONTROL OF AIR CONDITIONING
Air conditioning should be kept under sufficient control to meet the standards for temperature and humidity. Dehumidifiers using desiccants may be used if they are equipped with filters capable of removing dust particles and maintaining relative humidity as prescribed in ANSI/AIIM IT 9.2 - 1991 Imaging Media - Photographic Processed Films, Plates, and Papers - Filing Enclosures and Storage Containers. Humidification before storage is not necessary unless the relative humidity in storage areas is less than 15 percent for long periods of time. Water trays or saturated chemical solutions should not be used because of the serious danger of over-humidification.
9.6 PROTECTION AGAINST AIR-ENTRAINED IMPURITIES
Solid particles that abrade film or react on the image should be cleaned from the air supplied to microfilm storage and associated rooms by the use of dry media mechanical filters or electrostatic precipitators. These filters should have an arrestance or cleaning efficiency of at least 80 percent when tested with atmospheric air in accordance with ANSI PH1.43-1981 which cites the report to the National Board of Fire Underwriters for the installation of air conditioning, air heating, air cooling, and ventilating systems. If used, filtering media, casings and castings should be of the non-combustible type.
9.7 GASEOUS IMPURITIES
Such gaseous impurities as sulfur dioxide, nitrous oxide, peroxide and hydrogen sulfide that may cause deterioration of microfilm should be removed form the air. Silver-gelatin microfilm should not be stored with other types of film, either in the same room or in rooms connected by ventilating ducts, because gases given off by the non-silver - gelatin microfilm may damage or destroy the safety bases film.
9.8 MICROFILM INSPECTION
At approximately two year intervals, a sample of randomly selected rolls of microfilm should be inspected according to MS45 - 1990 Recommended Practice for Inspection of Stored Silver-Gelatin Microforms for Evidence of Deterioration. For each biennial, inspection of different lot sample should be chosen allowing some over-lapping to note any changes in previous inspected samples. The film should be inspected for mold or fungus, excessive brittleness, film curl or discoloration, adherence of the emulsion to the base, evidence of adhesion, and the presence of redox blemishes (measles). A re-reading of resolution test targets and a re-measurement of the film density should be made. Film boxes and reels used to store the film should also be inspected for any evidence of deterioration. The inspection report should include the (a) quantity of microfilm of public records on hand, i.e. number of rolls, microfiche jackets etc.; (b) quantity and identification of microfilm inspected; (c) condition of the microfilm; and (d) corrective action required if necessary. If deterioration is found, corrective action will require more extensive inspection to locate all deteriorating film. If required, please contact Imaging Services Branch for additional information.
An agency having microfilm of public records should prepare a silver duplicate to replace the original when it finds that the original copies are deteriorating. Obviously, the replacement should comply with all the aforementioned requirements.
SOURCES OF ADDITIONAL INFORMATION
Association for Information and Image Management (AIIM)
1100 Wayne Avenue
Silver Spring, Maryland 20910
Voice: 301-587-8202
Fax: 301-587-2711
American National Standards Institute (ANSI)
1430 Broadway
New York, New York 10018
212-354-3300
National Center for State Courts (NCSC)
Publications Manager
300 Newport Avenue
Williamsburg, Virginia 23187-8798
888-450-0391
The Library of Virginia (LVA)
Archives and Records Management Services Division (ARMS)
800 E. Broad Street
Richmond, Virginia 23219
804-692-3600
GLOSSARY
- ANSI.
- American National Standards Institute. ANSI is composed of representatives from industry, technical societies, consumer organizations and government agencies.
- Aperture card.
- A card with a rectangular hole(s) designed for holding one or more frames of microfilm.
- Archival quality.
- The ability of a processed microform to retain its original characteristics and resist deterioration over time in use and in storage.
- Base.
- A transparent plastic material, usually of cellulose triacetate or polyester, upon which a photographic emulsion or other material may be coated.
- Book cradle.
- A device which holds a large bound book open and flat during filming with a planetary camera.
- Camera microfilm.
- First generation microfilm. The microfilm that comes out of the camera, as opposed to microfilm created by duplication.
- Camera-processor.
- A device which performs both filming and processing within one unit.
- Cartridge.
- A single core container enclosing roll film, designed to be inserted into microfilm viewing devices.
- Cassette.
- A double core container enclosing roll film. Designed to be inserted into microfilm viewing devices.
- Cellulose ester.
- A film base composed mainly of cellulose esters of acetic, propionic or butyric acids or mixtures thereof.
- Cine mode.
- Images of microfilm oriented with information in a sideways position.
- Comic mode.
- Images on microfilm oriented with information in an upright position.
- Computer output microfilm (COM).
- Microfilm containing data produced by a recorder from computer-generated signals.
- Densitometer.
- The device used to measure the density of microfilm.
- Density.
- The light-absorbing or light reflecting characteristics of a photographic image.
- Diazo film.
- A non-reversing duplicate film (containing diazonium salts) which forms an image when exposed to ultraviolet light and enveloped by ammonia.
- Dry-process silver film.
- A non-gelatin silver film that is developed by application of heat.
- Duplicating microfilms.
- Microfilm designed for the creation of duplicate microforms rather then for use in cameras.
- Emulsion.
- The light-sensitive coating on microfilm, usually containing silver salts and other chemicals suspended in gelatin.
- Exposure.
- The process of subjecting light sensitive film to a lighted object.
- Eye loupe.
- A small low-power magnifying device.
- Generation.
- A measure of the remoteness of a particular copy from the original material. The picture taken of a document, cathode ray tube, or other item, is termed first generation microfilm (camera microfilm). Copies made from this first generation are second generation, copies from the second generation are third generation, etc.
- Hardcopy.
- (1) An enlarged reproduction from a microfilm usually on paper. (2) A printed copy of machine output in a readable form, for example, output form a computer printer.
- Image.
- ( 1) A reproduction of an object, produced by light rays. (2) A photographic reproduction of an object on film.
- Jacket.
- A transparent plastic carrier with sleeves or channels to hold frames of microfilm.
- Light box.
- A device for inspecting microfilm which provides even light over the viewing area.
- Master film.
- Any film, but generally a negative, used solely for making copies, as opposed to film which may be used in readers.
- Methylene blue.
- A chemical dye formed during the testing of archival permanence of processed micro-images using the methylene-blue method.
- Microfiche.
- A sheet of microfilm which rows of microimages in a grid pattern.
- Microfilm.
- Fine-grain, fine-resolution photographic film carrying, or designed to carry, photographic images greatly reduced in size and usually too small to be read by the unaided eye.
- Microform.
- A generic term for any form, usually film, that contains micro-images.
- Negative-appearing image.
- An image in which the lines and characters appear light against a dark background.
- Planetary camera.
- A type of microfilm camera in which the document being photographed and the film remain in a stationary position during the exposure. The document is on a plane surface the time of filming. Also known as a flatbed camera.
- Polarity.
- The condition of an image being positive or negative.
- Polyester.
- A transparent plastic made from polyesters and used as a film base because of its dimensional stability, strength, resistance to tearing and relative non-inflammability.
- Positive-appearing image.
- An image in which the lines and characters appear dark against a light background.
- Processing.
- The treatment of exposed film to make the latent image visible and usable through a series of usually five steps, i.e., developing, washing, fixing, washing, and drying.
- Redox blemish.
- A micro-spot formation on silver-gelatin type films caused by air pollution, improper packaging or storage conditions.
- Reduction ratio.
- The linear ratio of the side of the original document to the size of the microfilm image.
- Residual thiosulfate (hypo).
- Residual hypo from the processing state which remains in the film after washing. Excess residual hypo can cause the film to deteriorate prematurely.
- Resolution.
- The ability of a camera or film to record fine detail. A measure of the sharpness of an image, expressed as the number of lines per millimeter discernable in an image.
- Roll microfilm.
- A length of microfilm on a reel, spool or core normally 100 or 200 feet in length.
- Rotary camera.
- A type of microfilm camera where the document is fed into the camera, and the document and film both move during exposure.
- Safety film.
- A comparatively nonflammable film support (base) that meets ANSI requirements for safety film.
- Silver film.
- A film which is coated with a silver halide emulsion.
- Silver halide.
- A compound of silver and one of the following elements known as halogens: chlorine, bromine, iodine, fluorine.
- Splice.
- To join two pieces of film together by cementing or welding to form one continuous piece.
- Step and repeat camera.
- A type of microfilm camera which produces microfiche by exposing a series of separate images on 105mm film in an orderly row and column format.
- Target.
- Any document or chart containing identification information, coding or test charts.
- Ultrafiche.
- Microfiche with images reduced more than 90x.
- Vesicular film.
- Duplicate film type which forms a latent image when exposed to ultraviolet light and procedures a fixed image when subjected to heat.