A continuous method for producing halftone images comprising:1. image-wise exposing a lith-type silver halide photographic material comprising a silver halide emulsion with not less than about 85 mol% silver chloride and not more than about 8 mol% of silver iodide and containing at least one organic silver complex compound which is substantially insoluble in water in contiguous relationship with a photosensitive silver halide emulsion which contains not less than 60 mol% silver chloride and which is chemically and spectrally sensitized; and2. developing the photographic material in a continuous fashion with a developer containing hydroquinone and a carbonyl-bisulfite adduct in the presence of a polyalkylene oxide of a molecular weight not less than 1000.