Model Investigation of the Effect of Cd- and Cu- Ions on the Photographic Process

Abstract

The deposition of foreign substances on silver halide single crystals by means of vacuum evaporation mokes it possible to study their effect on the two stages of the photographic process-the latent image formation under exposure to light and the reduction of the exposed parts on development. The effect of cadmium, cuprous and cupric ions on the sensitivity of silver bromide crystals has been investigated. It was established that cadmium and cuprous ions promote the process of development and enhance the latent image formation. Cupric ions have a strong desensitizing effect on both stages of the photographic process. It was found that the metal ions investigated display a certain incompatibility with sulphur sensitizers. In spite of that, an appropriate concentration of cadmium ions was found to increase further the light sensitivity of silver sensitized crystals, promoting only the process of development.