The reverse would be a negative. A file that contains information on screen angle, resolution, page size and device-specific information for a file to be printed on a PostScript device. In color reproduction, a proof of a color subject on a printing press, using the same color inks and paper stocks on which the final run will be done on. This proof is done prior to the final reproduction and is the only true and predictable way to show proof of what is contained in the litho films. There is no other proof system that takes into account printing aspects such as absorbency of stock, hue of inks, trap and other printing mechanics which occur on a press.
Additive primaries are red, blue and green.
The subtractive primaries are cyan, magenta and yellow. Inside a laser printer, the mechanism that uses a laser to create an electrostatic image of a page and transfers it onto a sheet of paper. The list includes the file currently printing and those waiting to be printed. In printing, the subtractive primary process ink colors are cyan, magenta, yellow plus black in four color process printing. Proofs made from separate plates in process work, usually during a press proof, showing the sequence of printing and the result after each additional color has been applied.