A crowded-monolayer emulsion is viewed in one dimension as an alternating renewal process. The model presented is sufficiently general to include the effects of arbitrary distributions of halide grain sizes and gap sizes and further arbitrary dependence of developability of the grains on grain size and exposure. In an example, we calculate the increase of granularity that accompanies the increased exposure latitude obtained by broadening the size distribution of maximally sensitized grains.
P. E. Castro, J. H. B. Kemperman, and E. A. Trabka, "Alternating renewal model of photographic granularity," J. Opt. Soc. Am. 63, 820-825 (1973)