Patent US 4,430,668

A method and apparatus for producing color graphic images wherein color graphic data is input to a computer programmed to produce sequentially black and white images on a cathode ray tube representing respectively the images of cyan, magenta, yellow and black internegatives to be produced. The images are photographed sequentially as presented which upon development produce internegatives corresponding to cyan, magenta, yellow and black. The image may alternatively be output to a printer. The four negatives are then employed in a four color printing process to create control plates for use in the cyan, magenta, yellow and black units of a printing press.