A Comparison between the GCA/GATF off-press proof comparator and the GATF standard offset color control bar for identifying when a cromalin off-press proof is prepared to specification for web offset publication
Off-press proofing is a method of simulating the way a set of separation negatives or positives will look when printed without having to go to the printing press. In 1965, The Graphic Arts Technical Foundation (GATF) developed a proofing control device for production Lithography. The Standard Offset Color Control Bar was also utilized for off-press proofing. In 1983, The Graphic Communications Association, in cooperation with GATF, introduced The Off-Press Proof Comparator. This control device was designed specifically for this technology and intended to be used by both technical and non-technical personnel with equal and successful results. This thesis is concerned with the accuracy of both proofing bars using the Du Pont Cromalin system of off -press proofing to determine whether one control bar is better for judging whether a proof is made correctly to SWOP standards. It is also concerned with whether one control bar is more versatile than the other for both technical or non-technical personnel to use. The experiment consisted of a total sample population of forty experts from four different fields of the graphic arts industry. These four groups represent technical and non-technical users. Each participant was asked to look at samples of each color bar and choose which sample was made to SWOP standards. The results were applied to statistical methods of evaluation to give a final result. The final results of this thesis support The Graphic Communications Association's claim that the Off-Press Proof Comparator in not only more accurate, but also more versatile for all members of the graphic arts community. The implications of this thesis are that a "master" comparative device can aid in evaluating if proofs are made correctly- A pictorial element is a helpful reference tool when used in conjunction with the "master" comparative device. A greater emphasis needs to be placed on viewing off-press proofs under corrected viewing conditions.
Library of Congress Subject Headings
Color printing--Evaluation; Color separation--Evaluation; Proofs (Printing)
Department, Program, or Center
School of Print Media (CIAS)
Breakstone, William F., "A Comparison between the GCA/GATF off-press proof comparator and the GATF standard offset color control bar for identifying when a cromalin off-press proof is prepared to specification for web offset publication" (1990). Thesis. Rochester Institute of Technology. Accessed from
RIT – Main Campus