Emulsion microcrystals of the AgX type are widely used in modern photographic science and technology. AgBrI or AgClI model were supported by characterizing those centers on octahedral and cubic silver bromide-chlolide emulsion grains with equivalent circular diameter of 0.2 μm. There have been more strict requirements for silver halide emulsions for photographic use, which has increased the demands for the high level photographic characteristics such as, for example, high speed, excellent graininess, high sharpness, low fog, wider exposure latitude range and so on. Crystallizations of AgBrI and AgClI are studied.