The Measurement of Density in Variable Density Sound Film

The dependence of the optical density of developed photographic materials upon the method of its measurement was first demonstrated by Callier.¹ He discussed the effect of light scattering by the photographic image and presented data which seemed to justify the empirical relation: $D||\, = QD\parallel\!\!\!\!\!-$ where $D||$ (specular density) is the value obtained with the developed image in a specular beam, $D\parallel\!\!\!\!\!-$ (diffuse density) the value obtained with diffuse illumination, and Q a constant factor greater than unity.

Print ISSN

0097-5834

Published

1930-09

Content type

Original Research

DOI

10.5594/J06549