film development

film development, the processing of photographic or x-ray films to manifest the latent image resulting from exposure of the chemically treated emulsion to electromagnetic radiation. Development involves wetting the film to loosen the emulsion, followed by a series of chemical baths that reduce the exposed silver ions to black metallic silver. The reducing agents for radiographic films generally contain hydroquinone to produce black tones slowly and phenidone to produce shades of gray rapidly.