Abstract

The optimum rendition of colors in a photographic color transparency requires an illuminator which provides adequate amounts of energy in the blue, green, and red regions of the spectrum. A criterion has been found which determines whether this condition is satisfied by a light source. The luminance level of illuminator viewing panels should be high enough so that shadow details are seen properly. The optimum luminance is approximately 400 footlamberts. The chromaticity should be such that the illuminator appears white. For average viewing conditions, a light source having the relative spectral energy distribution and chromaticity of a complete radiator at 4000 K has been found to be highly satisfactory. Best results will be obtained when the chromaticity of the light in the room where the illuminator is used is the same as that of the illuminator. The same spectral and chromaticity requirements apply to illuminants for viewing reflection color prints.

© 1953 Optical Society of America

The Relative Photographic Efficiency of Certain Light Sources*

Robert N. Wolfe and Francis H. Milligan
J. Opt. Soc. Am. 43(9) 791-797 (1953)

Spectral Energy Distribution of the International Commission on Illumination Light Sources A, B, and C*

Raymond Davis, Kasson S. Gibson, and Geraldine Walker Haupt
J. Opt. Soc. Am. 43(3) 172-176 (1953)

Measurement of Color Appearance

R. W. G. Hunt
J. Opt. Soc. Am. 55(11) 1540-1551 (1965)

Spectral Sensitivity of the Fovea. I. Neutral Adaptation

Leo M. Hurvich and Dorothea Jameson
J. Opt. Soc. Am. 43(6) 485-494 (1953)

Application of a Color-Difference Index to Highly Selective Transparent Specimens

A. C. Webber and F. W. Billmeyer
J. Opt. Soc. Am. 43(12) 1127-1136 (1953)