Tuesday, June 23, 2009

Non-print equipment & services: Microforms

Required Reading:
Choosing microform readers and reader/printers
South Carolina Department of Archives and History Archives and Records Management division

Conserve space
Wide range of materials
Improved services
Easily converted to print with reader-printer
Less mutilation
Easily replaced

Specialized equipment/environment required
Equipment maintenance
Variety of standards
Lack of colour
Lack of bibliographic control
User resistance

An optical information storage medium that contains photographically reduced images.

16mm width of choice for business-oriented applications, technical and industrial libraries
35mm most common size in libraries

A card-shaped sheet of photographic film, usually 3 x 5 or 4 x 6 inches in size, designed to store miniaturized text and/or microimages arranged in a two-dimensional grid pattern. Various formats exist, but ISO recommends 75 x 125 mm (48 frames in four rows of twelve) or 105 x 148 mm (60 frames in five rows of twelve). Although each sheet usually includes a title, index number, or other heading across the top which can be read without magnification, the text itself can be read and copied only with the aid of a microform reader-printer machine. ODLIS

A sheet of opaque material, such as paper or card stock, bearing miniaturized text and/or microimages in a two-dimensional grid pattern, which can be magnified and copied only with the aid of special equipment. Microform reader-printer machines are usually available in libraries with microopaque holdings for viewing and making hard copies. ODLIS

Silver gelatin
Most popular camera film for source department microphotography
Also known as “silver halide microfilm”
Inappropriate storage can result in redox blemishes

Intended for exclusively for duplication and is most widely used type of film for duplication
Depending on dye used will appear black, blue or sepia
Some types long-term (100 year) potential; some types medium-term (10 year) potential
Will eventually fade, even if stored in the dark. Prolonged exposure to light accelerates fading.

Uses a process involving exposure to ultraviolet light and development by heat
Limited to duplication function
Normally results in reverse polarity of microform being duplicated and most widely used in COM applications where the master is positive and negative working copies are desired
Readily identified by their beige, gray or light blue colour
Some long-term; some medium-term potential
May produce hydrochloric acid

ANSI levels of stability

Long-term100 years
Medium term10 years

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