Details:
Summary:
A 3-D convex hull program, Qhull, was applied to data sets consisting of the Neugebauer primaries and selected multicolor traps of 4-, 5- and 6-color printing systems. Program output was plotted as polytopes, curved surface solids or wireframes in CIE Lab space in full color. These produced a 3-D representation of a lithographic printing gamut. Superposition of two or more gamuts affords users full color visual feedback of where, what color and how much color enhancement was brought about by changes of inks or stocks. These techniques provide far more detail than traditional 2-D gamut plots. Quantitative estimates of gamut volumes compared the color reproduction potential of several sets of fluorescent process printing inks. The input of many hundreds of halftone data points from IT8 charts were processed with the same ease as a sparse set of Neugebauer primaries. This produced a more accurate gamut on convex surfaces and some improvement in the accuracy in volumes.