The Dual Mechanism of Latent-Image Formation In Photographic Emulsions^*

* ommunication No. 2159H from the Kodak Researh Laboratories.

Abstract

Unsensitized sliver-bromide emulsions are shown to have greater low-intensity reciprocity failure for exposures to blue light than to minus-blue light. This difference of reciprocity-failure behaviour Increases with groIn size but decreases or vanishes on spectral sensitization of the emulsions. It is shown that it is necessary to distinguish the (unction of chemical sensitization at high intensities from that at law intensities of exposure, The results are Interpreted on the basis of two different modes of formation of latent Image.

Notes

* ommunication No. 2159H from the Kodak Researh Laboratories.