Optimal reproduction of spot colors on a digital press

摘要

Digital presses manufactured by companies such as Hewlett-Packard, NexPress, and Xerox are rapidly gaining acceptance in the marketplace. Since these devices typically use four or a few more colors in their printing processes, the degree to which they can accurately simulate the larger gamut of spot colors is of considerable interest in many applications. Pantone licenses printers at the end of an extensive color evaluation and analysis procedure, during which a lookup table is developed, giving the optimal inking values for matching or simulating each color of the PANTONE MATCHING SYSTEM®. The stability of the printing process over time gets a thorough test during this procedure, which uses both instrumental and visual matching techniques. Gamut mapping algorithms used in commercial profile-building software were developed for the reproduction of images, which are ensembles of colors; they do not usually yield optimal results for the case of individual colors. Development work at Pantone is aimed at a better understanding of how a skilled colorist makes the decisions leading to an optimal simulation of a color.