Influence of Light Scattering in a Photographic Layer on the Exposure of the Uppermost Elementary Layer

Abstract

Theory and experiments show that the effective exposure in the uppermost elementary layer (i.e., the uppermost layer of grains) of a photographic emulsion coating is I+88R times (R=reflexion factor of the emulsion) as high as the exposure caused by an incident flux of “parallel” light. The experiments show that in determining the exposure increase by means of a substitute layer (which stands for the genuine elementary layer for the experiment) the physical properties of this layer are of decisive importance; an inappropriate choice of this layer will yield exposure values which are lower than those applying in the elementary layer.