What is duotone?
Duotone is the generic name for multitone printing, which can be done with two, three or four inks. This process requires that the press be set up with special inks, usually PANTONE-designated colors, instead of the standard CMYK inks used for process color printing. Usually the images are printed with a dark base color and a lighter second color, overprinted to fill in, tint and tone the photo or graphic.
Duotone color mode in Photoshop supports between one to four colors of ink. Because home inkjet printers are far better at printing full-color images than black and white, many photographers and designers use Photoshop Duotone processing to improve their artwork/prints. Photoshop's Duotone mode is also commonly used for creating sepia toned prints, using black and yellow inks, sometimes with a third color.
Full color original
Duotone with Pantone 276 & 106
Other multi-tone images
There are 4 types of multitone images in all. Each one contains the number of inks as the name implies:
- Monotone grayscale images printed with a single ink
- Duotone grayscale images printed with two inks
- Tritone grayscale images printed with three inks
- Quadtone grayscale images printed with four ink
Making a duotone image in Photoshop
You can use any CMYK or RGB image and turn it into a duotone. First step is to make it a grayscale image. Go to Image > Mode > Grayscale. Then access the same menu and click duotone.
Duotone options dialog screen
In the duotone menu you can pick upto 4 colors or Pantone's and load or safe any color combinations you make.
Duotone curves screen
The curves for your selected duotone offer a lot of influence of the usage of inks in different depths of tone in the image.
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