Spot colors are special premixed inks used instead of, or in addition to, the process color (CMYK) inks. Each spot color requires its own plate on the press. (Because a varnish requires a separate plate, it is considered a spot color, too.)

If you are planning to print an image with spot colors, you need to create spot channels to store the colors. To export spot channels, save the file in PSD or TIFF file formats as they are smaller in size and more efficient to work with.

Note the following when working with spot colors:

• For spot color graphics that have crisp edges and knock out the underlying image, consider creating the additional artwork in a page layout or illustration application.

• To apply spot color as a tint throughout an image, convert the image to Duotone mode and apply the spot color to one of the duotone plates. You can use up to four spot colors, one per plate.

• The names of the spot colors are printed on the separations.

• Spot colors are overprinted on top of the fully composited image. Each spot color is printed in the order it appears in the Channels panel, with the topmost channel printing as the topmost spot color.

• You cannot move spot colors above a default channel in the Channels panel except in Multichannel mode.

• You cannot apply spot colors to individual layers.

• Printing an image with a spot color channel to a composite color printer will print the spot color at an opacity indicated by the Solidity setting.

• You can merge spot channels with color channels, splitting the spot color into its color channel components.

Create a new spot channel

You can create a new spot channel or convert an existing alpha channel to a spot channel.

Convert an alpha channel to a spot channel

Edit a spot channel to add or remove color

Change a spot channel’s color or solidity

Merge spot channels

In RGB or CMYK color mode, you can remove spot channels and merge them into the standard color channels. When you merge spot channels in CMYK mode, the resulting colors usually don’t precisely match the original spot colors, because CMYK inks can’t produce the range of colors available from spot color inks.

Adjust overlapping spot colors

To prevent overlapping spot colors from either printing over or knocking out the underlying spot color, remove one of the spot colors where they overlap.

Use a printed sample of the overprinted inks to adjust your screen display to help you predict how colors will look when printed.