Process for controlling tone reproduction

Abstract

The principal task in graphic arts reproduction is to convert input images, such as continuous tone original images, into output images, such as half-tone images, to permit, for instance, the creation of half-tone prints on a printing press. In this process, tones (i.e., shades of gray) from the original image are typically altered or affected in two important ways. First, the printing conditions substantially affect production of an optimized half-tone representation (or match copy) of the original continuous tone image. Second, the operator often needs to modify certain tones from that in the original to bring out more or less detail to achieve a desired artistic effect. This invention allows the operator to determine and adjust for printing conditions and original tone quality in a particular system and under a particular set of operating conditions, thus greatly reducing the time-consuming experimentation that operators have previously had to endure to obtain acceptable results.