Method and apparatus for making reproductions of color film frames

US4274732A · kind A · utility

Assignee

• AGFA-Gervaert AG · DE

Inventors

• Siegfried Thurm · Meerbusch, DE
• Konrad Bunge

Key dates

• Filing date: Jan 22, 1979
• Grant date: Jun 23, 1981
• Expiry date: Jan 22, 1999

Classification

• Technology area (CPC G): Physics
• CPC primary: G03B27/735
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The exposed and developed frames of a color film are copied on the basis of information which is obtained by scanning the density of each frame in primary colors as well as on the basis of information which is obtained by imaging a series of gray filters having different densities onto one or more portions of the film outside of the film frames and scanning the density of the image of each filter. The information which is obtained as a result of such scanning is processed by a computer or an amplifier which controls the quantity of copying light in each of the primary colors, either by selecting the interval of exposure of each frame to light in each of the primary colors by controlling the intensity of light in each of the primary colors (if the exposure times in each of the primary colors are identical). The filters can be imaged prior to exposure of frames to scene light and/or shortly prior to development of the film in a processing laboratory. The difference between the results of scanning of filter images which are exposed prior to exposure of frames to scene light and the results of scanning of filter images exposed immediately or shortly prior to development of the film is …