Abstract: A processing composition includes a combination of two different mercapto-substituted anti-sludging agents. The first compound is a conventional mercapto-substituted compound, and the second compound is a mercapto thiadiazole glycerol propoxylate having the formula I: ##STR1## This processing composition can be used to provide black-and-white development of both color reversal and black-and-white photographic elements, and particularly in high contrast graphic arts films.

Abstract: An improved photographic developing composition, for use in development of a black-and-white silver halide photographic element, is comprised of at least one developing agent and, in an amount sufficient to inhibit sludge deposition, a polyoxyalkylated phosphate ester. The developing composition is broadly useful in black-and-white development but is most advantageously employed in a process for forming a high-contrast image utilizing a silver halide photographic element comprising a hydrazine compound which functions as a nucleating agent and an amino compound which functions as an incorporated booster.

Abstract: High contrast development of photographic elements, such as lithographic films used in the field of graphic arts, is carried out in the presence of a hydrazine compound with an aqueous alkaline developing solution which has a pH of above 10 and below 12 and contains a dihydroxybenzene developing agent, a 3-pyrazolidone developing agent, a sulfite preservative, and a contrast-promoting amount of an amino compound. The developing solution combines the advantages of high capacity, a high degree of stability, and a long effective life, while providing excellent contrast and speed characteristics.