A Simplified Motion-Picture Laboratory Control Method for Improved Color Duplication

Motion-picture laboratories contend with several sources of variability in producing consistent, high-quality prints, especially in the case of color reversal intermediate (CRI) and interpositive-duplicate negative duplicating systems. What has been lacking is a simple, inexpensive, easily implemented, and universally adopted control method for the production of interpositives and duplicate negatives from negative originals. We propose a control method based upon the concept of LAD — Laboratory Aim Density. A standard film patch is specified at densities midway between the minimum and maximum typically obtained for normal camera exposure. All other material in a production (regardless of film type or origin) is timed with respect to this standard patch. Laboratory Aim Densities are specified, and tolerances are suggested, for the print-through of the standard patch for each film type onto which the original or intermediates may be printed. These Laboratory Aim Densities are chosen to be at the center of the usable straight-line portions of the duplicating film's characteristic curves. Within the tolerances of normal film, printer, and process variability, consistent duplicates having good tone and color reproduction characteristics will be obtained from the original. This method may be adapted also for obtaining color internegatives from reversal camera film originals.

Print ISSN

0036-1682

Published

1976-10

Content type

Original Research

DOI

10.5594/J07544