Preprogrammed and Automatic Color Correction for Telecine

Both preprogramming and automatic correction are in operational use in the BBC. It has been found that despite the care which is taken during filming and printing, variations of exposure and color from shot to shot are such that preprogramming is often necessary if fully satisfactory results are to be achieved. Preprogramming entails recording the settings of the color-correction controls determined during rehearsal and recalling those settings during transmission of the film so that they are applied to the correction unit at the same time as the error occurs. Automatic correction is provided by a unit which applies correction automatically to the red, green and blue signals at the output of the telecine. This unit allows different modes of operation (which may be selected separately): automatic black-level, automatic color balance, and automatic gain. The primary use of automatic correction has been for news film shot on reversal stock. Another promising field is the replay of old feature films which are, in some cases, of rather poor quality.

Print ISSN

0361-4573

Published

1974-08

Content type

Original Research

DOI

10.5594/J13450