Computation of Halftone Color Gamuts of Process Inks.

The gamut of colors of sets of process inks can be calculated with sufficient accuracy by using the Neugebauer equations. In this paper the gamut is represented by plotting darkness against color saturation with hue approximately constant. This allows different ink sets to be compared at any given hue to see which ink set produces the greater saturation at various levels of darkness. The gamut is plotted in a color space that is more uniform than the CIE system so that a measure of visual differences can be associated with the differences between plotted gamuts. The proposed method of plotting color gamuts will be illustrated using two ink sets. Also, the gamut differences for an ink set printed on newsprint and on higher quality paper will be plotted by this method. The increase of gamut by the addition of a black ink is also shown. A comparison between inks presently used and the so-called ideal inks is also discussed.