Sensitizers silver halide light sensitivity

Silver Halide Light-sensitive compound used in photographic film and paper. 

All the silver halides are sensitive to light, decomposing eventually to silver. In sunlight, silver chloride turns first violet and finally black. The use of these compounds in photography depends on this (see below). (All silver salts are, in fact, photosensitive—the neck of a silver nitrate bottle is black owing to a deposit of silver.)... 

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