Abstract:

The effect of three practical variables on sensitivity at low irradiance of a silver iodobromide emulsion coating was investigated, including the composition of the gelatin added in the emulsion during chemical ripening, the treatment of the emulsion coatings with the vacuum-outgasing and the extension of the developing time of the layer. The results show that the sensitivity at low irradiance increases with increasing the proportion of the active constituent in the additional gelatin and extending the developing time, but the fog also rises. In the other hand, the variances of sensitivity and fog of the vacuum-treated coatings during chemical ripening are different from ones of general untreated coatings with the vacuum-outgasing. It seems that the treatment of the emulsion with the vacuum-outgasing opens up possibilities for reducing low-intensity reciprocity failure.