Abstract: High contrast photographic images suitable for lithographic use are obtained with stable (nonlithographic) developers when iodide is released from a surface-sensitized iodobromide emulsion to induce development of the exposed areas in an internally sensitized core-shell emulsion. A bromoiodide or trihalide core is produced by balanced double jet precipitation, then the core is chemically sensitized and covered with a chlorobromide or chloride shell by balanced double jet precipitation or preferably by a cyclic pAg addition technique. The core-shell emulsion must have a sensitivity equal to or greater than the surface sensitized emulsion.