Abstract: The invention is generally accomplished by providing nucleation of silver halide crystals or grain without backmixing or exposure to previously nucleated grains. Generally this is accomplished by injecting a solution of silver nitrate into a solution of sodium bromide and peptizer as it is moving in pipe in a type of flow which does not provide back mixing and moves in generally plug flow. The plug flow is carried out until nucleation is complete and then the nucleated grains are transferred to a mixing container where they are ripened, grown, and subjected to the normal treatments, such as sensitization, applied to the silver halide to be used photgraphically.