Toning
Altering the color of a print or digital image that was originally in black and white. In the practice of conventional photography, black-and-white photos are often toned by transforming the metallic silver present in the print emulsion into a silver compound. This process is known as "toning." This is something that takes place in sepia and selenium toning. Metal-replacement toners are another type of toner that can be used in procedures such as platinum and gold toning. By applying the appropriate post-processing techniques, similar effects can be created in digital photographs.
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