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Optical Engineering

Contrast-Computing Darkroom Exposure Meter
Author(s): Waldemar H. Lehn; R. H. Cook
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Paper Abstract

A darkroom exposure meter has been designed to compute from a single measurement sequence both the exposure time and the paper contrast necessary to accept the full tonal scale of the negative. The photographer moves a phototransistor probe across the projected image to sample all areas that are to show gradation in the finished print. A microcomputer accepts the digitized probe output, compares the whole range of readings with paper characteristics stored in its memory, and calculates contrast grade and exposure time. A prototype constructed on this basis has demonstrated the feasibility of this concept. Such a device can greatly improve darkroom productivity.

Paper Details

Date Published: 1 May 1989
PDF: 3 pages
Opt. Eng. 28(5) 285544 doi: 10.1117/12.7976995
Published in: Optical Engineering Volume 28, Issue 5
Show Author Affiliations
Waldemar H. Lehn, University of Manitoba (Canada)
R. H. Cook, University of Manitoba (Canada)

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