Phototypesetting

Phototypesetting is a method of setting type, rendered obsolete with the popularity of the personal computer and desktop publishing software, that uses a photographic process to generate columns of type on a scroll of photographic paper. Typesetters use a machine called a phototypesetter, which quickly projects light through a film negative image of an individual character in a font, through a lens that magnifies or reduces the size of the character onto photographic paper, which is collected on a spool in a light-tight canister. The photographic paper or film is then fed into a processor, a machine that pulls the paper or film strip through two or three baths of chemicals, where it emerges ready for paste-up or film make-up.

Phototypesetting machines project characters onto film for offset printing. In 1949 the Photon Corporation in Cambridge, Mass. developed equipment based on the Lumitype of Rene Higonnet and Louis Moyroud. The Lumitype-Photon was first used to set a complete published book in 1953, and for newspaper work in 1954.Mergenthaler produced the Linofilm using a different design, and Monotype produced Monophoto. Other companies followed with products that included Alphatype and Varityper.

The major advancement presented by the phototypesetting machines over the Linotype machine hot-type machines was the elimination of metal type, an intermediate step no longer required once offset printing became the norm. This cold-type technology could also be used in office environments where hot-metal machines (the Mergenthaler Linotype, the Harris Intertype and the Monotype) could not. The use of phototypesetting grew rapidly in the 1960s when software was developed to convert marked up copy, usually typed on paper tape, to the codes that controlled the phototypesetters.

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