The purpose of this study was to compare the quality of PostScriptgenerated four-color halftones to halftones produced by traditional high-end color systems. The quality issue is one that must be addressed before a decision can be made to move magazine production onto a complete desktop publishing platform. In moving layout and design functions onto a desktop publishing platform, publishers can take advantage of PostScript as a page-description language to electronically create complete pages. Electronic assembly would eliminate the mechanical stripping step, allowing great reductions in prepress manufacturing costs. There are two routes that can be taken to output these electronic pages. First, the pages can be output via the traditional high-end color systems, like those marketed by companies such as Dupont Imaging Systems and Scitex. These systems, though expensive to purchase and maintain, are proven in terms of quality for four-color output. The alternative to the high-end method is to output pages through device-independent PostScript-driven imagesetters, like those marketed by companies such as Agfa and Linotype. These devices are low-cost in comparison to the high-end systems. The quality, however, is the subject of debate. To highlight the differences in quality, the same continuous-tone data generated from a high resolution scanner was sent for halftone film output through both a high-end imagesetter and a PostScript-driven imagesetter. The images were shown to two groups of viewers: professionals (from the printing and publishing industry) and non-professionals. The viewers were then asked questions pertaining to the sharpness, detail, contrast, tonal range, and overall pleasing color of the two sets of images. For each group, the responses were analyzed statistically to determine if there was a perceived difference between four-color images generated from a high-end color system and those generated from PostScript-driven output devices. In addition, the responses of the two groups were compared statisticaUy to determine if there was a difference between the way the professionals viewed the two images and the way non-professionals viewed them. It was determined that within the group of professionals, there was no statistically meaningful difference perceived between the high-end color and the PostScript color. The same was found to be true for the non-professionals. However, when comparing the responses of professionals to non professionals, it was found that there was a statistically meaningful difference in the pattern of their responses, or in the way they viewed the imagesthough within each of these two groups, there was no statisticaUy apparent agreement on the preferences.
Library of Congress Subject Headings
Color printing--Analysis; Electronics in color printing; PostScript (Computer program language)
Department, Program, or Center
School of Print Media (CIAS)
Schneider, Mary Lee, "A Comparison of high-end color system halftones and postscript-generated halftones" (1991). Thesis. Rochester Institute of Technology. Accessed from
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