water spot

Definition: Defect on processed films caused by differences in drying rates due to uneven distribution of water. * Most often seen in negatives: a drop of water that is slow to dry tends (a) to leave gelatine that is slightly less compact that faster drying gelating, thus leaving a slight swelling in the emulsion; (b) to allow movement of silver particles through the wet gelatine, causing local change in density.

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