Learn how to mix colors and make selective color corrections in your image
Selective color correction is a technique used by high-end scanners and separation programs to change the amount of process colors in each of the primary color components in an image. You can modify the amount of a process color in any primary color selectively—without affecting the other primary colors. For example, you can use selective color correction to dramatically decrease the cyan in the green component of an image while leaving the cyan in the blue component unaltered.
Even though Selective Color uses CMYK colors to correct an image, you can use it on RGB images.
Click the Selective Color icon in the Adjustments panel.
Choose Layer > New Adjustment Layer > Selective Color. Click OK in the New Layer dialog box.
You can also choose Image > Adjustments > Selective Color. But keep in mind that this method makes direct adjustments to the image layer and discards image information.
Choose the color you want to adjust from the Colors menu in the Properties panel. You can also choose a Preset that you’ve saved.
In the Properties panel, choose a Selective Color preset from the Preset menu.
Select a method in the Properties panel:
Changes the existing amount of cyan, magenta, yellow, or black by its percentage of the total. For example, if you start with a pixel that is 50% magenta and add 10%, 5% is added to the magenta (10% of 50% = 5%) for a total of 55% magenta. (This option cannot adjust pure specular white, which contains no color components.)
Adjusts the color in absolute values. For example, if you start with a pixel that is 50% magenta and add 10%, the magenta ink is set to a total of 60%.
The adjustment is based on how close a color is to one of the options in the Colors menu. For example, 50% magenta is midway between white and pure magenta and receives a proportionate mix of corrections defined for the two colors.
You can also save the settings you make for the Selective Color adjustment and reuse the settings on other images.