Light Sources as an Integral Part of the Color Photographic System

Newton stated that we do not “see” colored objects, but only perceive the spectral energy of a light source after selective reflection or transmission by natural objects. A color recording system reacts similarly. Thus, the light source is a predominant part of any color recording system, such as color photography. Color films have no chromatic adaptation mechanism such as the eye has. They are balanced for a specific light source. Color-reversal film is generally used for newsgathering. It does not allow for color corrections after the initial exposure as with the negative-positive process. Newsgathering is done under all types of light sources. Lamp manufacturers are mainly concerned with photometric properties only, such as luminous efficacy and specific luminous flux. Recently they have started to consider also the CIE color rendering index. Until now, little attention has been paid to the light source as an integral part of a color recording system. The author discusses the properties of light sources in relation to and as an integral part of a color-reversal film-recording system. The photometric properties of light sources and their CIE color rendering index only refer to visual color perception and do not spell out the photographic properties of light sources. A proposal is made which permits the evaluation of light sources as an integral part of color photographic systems.

Print ISSN

0036-1682

Published

1977-08

Content type

Original Research

DOI

10.5594/J17865