All inks that are used for printing do not have the same darkness. For example, yellow is lighter than cyan. Neutral density is used to specify the darkness of a printing ink on paper. A neutral density of 0 is white (no ink). For process colors, the neutral densities vary, depending on the ink set—for example, EuroOffset or SWOP. For spot colors, neutral density can be explicitly specified. If a spot color is normal (non-opaque), neutral density can also be estimated from a given color.

Example of neutral densities for process colors:

The neutral density of a non-100-percent value can be calculated from the area coverage (0 percent–100 percent) and the neutral density of the ink. The neutral density of a composite color is the sum of neutral densities for all of the separations.

Set neutral density values in the Color Database Editor dialog box.