Microform
A microform is a scaled-down reproduction of a document, typically either photographic film or paper, made for the purposes of transmission, storage, reading, and printing. Three formats are common: microfilm, microfiche, and aperture cards. In addition to filming from original paper documents, equipment is available that accepts a data stream from a computer and directly produces a microform.
John Benjamin Dancer was one of the first to produce microphotographs in 1839, using the daguerreotype process. Microphotography was first suggested as a document preservation method in 1851 by the astronomer James Glaisher, and in 1853 by John Herschel, another astronomer. Systems that mount microfilm images in punched cards have been widely used for archival storage of engineering information.
The medium has numerous characteristics, including that it enables libraries to access collections without putting rare, fragile, or valuable items at risk of theft or damage.
Desktop readers are boxes with a translucent screen at the front on to which is projected an image from a microform. A microfilm printer contains a xerographic copying process, like a photocopier. To create microform media, a planetary camera is mounted with the vertical axis above a copy that is stationary during exposure. Conversions may be applied to camera output or to release copies.
Description
A scaled-down reproduction of a document is known as a microform. Typically, a microform is either photographic film or paper, and made for the purposes of transmission, storage, reading, and printing. Microform images are commonly reduced to about 4% or of the original document in diameter and more than 500X in size. For higher storage density, greater optical reductions up to 250X may be used.Three formats are common: microfilm, microfiche, and aperture cards. Microcards, also known as micro-opaques, a format no longer produced, were similar to microfiche, but printed on cardboard rather than photographic film.
In addition to filming from original paper documents, equipment is available that accepts a data stream from a computer and directly produces a microform; the system exposes film to produce images as if the stream had been sent to a line printer and the listing had been microfilmed. The process is known as computer output microfilm or computer output microfiche.
Types of microform media
Flat film
105 × 148 mm flat film is used for microimages of very large engineering drawings. These may carry a title photographed or written along one edge. Typical reduction is about 20, representing a drawing that is 2.00 × 2.80 metres, that is 79 × 110 in. These films are stored as microfiche.Microfilm
or 35 mm film to motion picture standard is used, usually unperforated. Roll microfilm is stored on open reels or put into cartridges. The standard lengths for using roll film is 30.48 m for 35 mm rolls, and 100 ft, 130 ft and 215 feet for 16 mm rolls. One roll of 35 mm film may carry 600 images of large engineering drawings or 800 images of broadsheet newspaper pages. 16 mm film may carry 2,400 images of letter-sized images as a single stream of microimages along the film set so that lines of text are parallel to the sides of the film or 10,000 small documents, perhaps cheques or betting slips, with both sides of the originals set side by side on the film.Aperture cards
s are Hollerith cards into which a square opening has been cut. A 35 mm microfilm chip is mounted in the hole inside of a clear plastic sleeve or secured over the aperture with adhesive tape. They are used for engineering drawings in all engineering disciplines. There are libraries of these containing over 3 million cards. Aperture cards may be stored in drawers or in freestanding rotary units. The key-punched holes enable them to be readily sorted using computers.Microfiche
A microfiche is a sheet of flat film, most commonly 105 × 148 mm in size, the same dimensions as the ISO A6 paper size. It carries a matrix of microimages commonly read left-to-right and then top-to-bottom. All microfiches are read with the text parallel to the long side of the fiche, though some tables may be rotated 90 degrees. Frames may be landscape or portrait in orientation. Along the top of the fiche is usually an eye-legible banner printed black-on-white, carrying bibliographic information including fiche number, title, series, publish date, and publisher.The most commonly used format for the contained microimages is a portrait image of about 10 × 14 mm. Office-size papers or magazine pages require a reduction of around 24:1. Microfiches may be stored in individual open-top envelopes. usually made of acid-free paper, which are put in drawers or boxes as file cards, or put into relatively big pockets and made to look like a book, or may be stored in specially-made binders with pages of pockets which show only the title bar of each fiche.
Ultrafiche
Ultrafiche is an exceptionally compact version of a microfiche, storing analog data at much higher densities,. They are typically used for storing data gathered from extremely data-intensive operations, or for storing a book containing several thousands of pages on a single fiche.Micro-opaques
Micro-opaques are opaque, non-reversed formats and require specialized readers that projects them using reflected light. Few companies manufactured them, two of the most famous are Microcard Editions Inc. and Readex Corporation, whose product names became synonymous with the medium. They were invented in 1948 by Fremont Rider and described in his book, The Scholar and the Future of the Research Library.History
Using the daguerreotype process, John Benjamin Dancer was one of the first to produce microphotographs, in 1839. He achieved a reduction ratio of 160:1. Dancer refined his reduction procedures with Frederick Scott Archer's wet collodion process, developed in 1850–51, but he dismissed his decades-long work on microphotographs as a personal hobby and did not document his procedures. The idea that microphotography could be no more than a novelty was an opinion shared in the 1858 Dictionary of Photography, which called the process "somewhat trifling and childish".Microphotography was first suggested as a document preservation method in 1851 by the astronomer James Glaisher, and in 1853 by John Herschel, another astronomer. Both men attended the 1851 Great Exhibition in London, where the exhibit on photography greatly influenced Glaisher. He called it "the most remarkable discovery of modern times", and argued in his official report for using microphotography to preserve documents.
A pigeon post was in operation during the Siege of Paris. René Dagron photographed pages of newspapers in their entirety which he then converted into miniature photographs. He subsequently removed the collodion film from the glass base and rolled it tightly into a cylindrical shape which he then inserted into miniature tubes that were transported fastened to the tail feathers of the pigeons. Upon receipt the microphotograph was reattached to a glass frame and was then projected by magic lantern on the wall. The message contained in the microfilm could then be transcribed or copied. By 28 January 1871, when Paris and the Government of National Defense surrendered, Dagron had delivered 115,000 messages to Paris by carrier pigeon.
The chemist Charles-Louis Barreswil proposed the application of photographic methods with prints of a reduced size. The prints were on photographic paper and did not exceed 40 mm, to permit insertion in a goose-quill or thin metal tube, which protected against the elements. The pigeons each carried a dispatch that was tightly rolled and tied with a thread, and then attached to a tail feather of the pigeon. The dispatch was protected by being inserted in the quill, which was then attached to the tail feather.
The developments in microphotography continued through the next decades, but it was not until the turn of the century that its potential for practical usage was applied more broadly. In 1896, Canadian engineer Reginald A. Fessenden suggested microforms were a compact solution to engineers' unwieldy but frequently consulted materials. He proposed that up to 150,000,000 words could be made to fit in a square inch, and that a one-foot cube could contain 1.5 million volumes.
In 1906, Paul Otlet and Robert Goldschmidt proposed the livre microphotographique as a way to alleviate the cost and space limitations imposed by the codex format. Otlet's overarching goal was to create a World Center Library of Juridical, Social and Cultural Documentation, and he saw microfiche as a way to offer a stable and durable format that was inexpensive, easy to use, easy to reproduce, and extremely compact. In 1925, the team spoke of a massive library where each volume existed as master negatives and positives, and where items were printed on demand for interested patrons.
In the 1920s, microfilm began to be used in a commercial setting. New York City banker George McCarthy was issued a patent in 1925 for his "Checkograph" machine, designed to make micrographic copies of cancelled checks for permanent storage by financial institutions. In 1928, the Eastman Kodak Company bought McCarthy's invention and began marketing check microfilming devices under its "Recordak" division.
Between 1927 and 1935, the Library of Congress microfilmed more than three million pages of books and manuscripts in the British Library; in 1929 the Social Science Research Council and the American Council of Learned Societies joined to create a Joint Committee on Materials for Research, chaired for most of its existence by Robert C. Binkley, which looked closely at microform's potential to serve small print runs of academic or technical materials. In 1933, Charles C. Peters developed a method to microformat dissertations, and in 1934 the United States National Agriculture Library implemented the first microform print-on-demand service, which was quickly followed by a similar commercial concern, Science Service.
In 1935, Kodak's Recordak division began filming and publishing The New York Times on reels of 35 millimeter microfilm, ushering in the era of newspaper preservation on film. This method of information storage received the sanction of the American Library Association at its annual meeting in 1936, when it officially endorsed microforms.
In 1937 Herman H. Fussler of the University of Chicago set up an exhibition of microform at the World Congress of Universal Documentation.
Harvard University Library was the first major institution to realize the potential of microfilm to preserve broadsheets printed on high-acid newsprint and it launched its "Foreign Newspaper Project" to preserve such ephemeral publications in 1938. Roll microfilm proved far more satisfactory as a storage medium than earlier methods of film information storage, such as the Photoscope, the Film-O-Graph, the Fiske-O-Scope, and filmslides.
The year 1938 also saw another major event in the history of microfilm when University Microfilms International was established by Eugene Power. For the next half century, UMI would dominate the field, filming and distributing microfilm editions of current and past publications and academic dissertations. After another short-lived name change, UMI was made a part of ProQuest Information and Learning in 2001.