Photographic Plates

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Plates, Photographic


photosensitive materials in the form of sheets of glass coated with an emulsion of silver-halide microcrystals uniformly distributed in gelatin. The glass must be colorless, smooth, and without visible defects. Photographic plates are made in various standard sizes, ranging from 4.5 × 6 to 50 × 60 cm.

Photographic plates are classified as either general purpose or special purpose, depending on their photographic properties. General-purpose plates are used for artistic and documentary photography and for various scientific and technical purposes. Plates of this type that are manufactured in the USSR have varying degrees of light sensitivity (from 22 to 350 GOST [State Standard] units), color sensitivity (orthochromatic, panchromatic, and isopanchromatic), and contrast (normal, high-contrast, and low-contrast).

Special-purpose plates are intended for scientific and technical use and fall into the following subgroups: (1) diapositive—non-sensitized, low-sensitivity, and high-contrast; (2) reproduction— high-contrast; (3) micro (for photomicrography)—high-definition orthochromatic; (4) astronomical—high-sensitivity and high-contrast; (5) spectral UV—with increased sensitivity to violet and ultraviolet rays; (6) infrachromatic—sensitive to infrared rays; and (7) phototheodolite—orthochromatic, high-contrast, high-definition, and high-resolution.

All photographic plates are packaged in cardboard boxes with opaque packing. General-purpose plates are processed with general-purpose developers, but most special-purpose plates require special developers. A photographic plate’s emulsion swells in water and photographic solutions and can melt at 37° -40°C. For this reason, the use of photographic plates at higher temperatures is not recommended.


Kraush, L. Ia. Fotograficheskie materialy. Moscow, 1971.


References in periodicals archive ?
In the case of Atget, rescued from oblivion by Szarkowski via thousands of photographic plates held privately by the American photographer, Berenice Abbott, his sense of isolation and privacy, linked to his poverty made him a figure of mystery about whom so little is known today.
This was most unusual and a fine opportunity to use up some of the last remaining photographic plates.
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A handful of black-and-white photographic plates illustrate this meticulously documented historical text, embellished with a bibliography and index.
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Besides this, the eight chapters of text are enhanced by faultless line drawings and high quality b&w photographic plates which illustrate over 50 weapons and associated items.
The Unity Archives of the Moravian Church at Herrnhut, Saxony, include a collection of more than 1,000 photographic plates taken by missionaries in Labrador, besides a smaller collection that comes from Greenland.
He imbues his film with a smart, epigrammatic screenplay - there's a wonderful sequence in which Shackleton and Hurley (Matt Day), forced to destroy many of his photographic plates, pick and choose among them with fond if sardonic appreciation - and a gripping visual sense of how wrenching the expedition was (a man's toes are amputated in grisly close-up).
Virtually every page contains one or more illustrations--either drawn figures, photographic plates, or maps.
Based on the NIST results, image plates eventually may replace the expensive, hard-to-handle and often hard-to-obtain photographic plates traditionally used to record spectra at these wavelengths.

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