A duo image, made with black and blue colors in Photoshop
Duotone or duotone is the common name for multitone prints that are made with two, three or four colors.
Thanks to, among other things, Photoshop, duotone has become a generic term in photo editing for images that use color separation schemes. Normally this is a CMYK (Cyan, Magenta, Yellow, and Key (blacK)) separation, but in duotone it consists of two separations and can have any ink in offset printing.
HistoryDuotone comes from cyanotype and halftone prints. Color prints in newspapers and comic strips are usually halftone prints and sometimes duotone prints. Digital / modern use
The duotone color feature in Photoshop reaches between one and four color ink. Because with home inkjet printers, color images are printed far better than black and white images, many photographers use the duotone feature in Photoshop to enhance their grayscale for printing.
The Photoshop Duotone feature is also commonly used to create the sepia effect in an image. For this, black, yellow and sometimes a third color are used. Also see
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