Passport color

This article looks at passport color in printing. For the color scheme of passports, see passport .

Register cross printed with passport color with slight register difference

Passport color ( English registration black ) is a term from the printing industry and describes a color setting in which all colors involved in the printing process are 100% printed. It is used for registration marks (e.g. register crosses) and thus enables the assessment of exactly the right balance of the colors to one another ( register difference ). The color appears black, but in contrast to "normal" black in the CMYK color model , it consists not only of the black component (key), but of all the color components used in the respective printing process. If you look closely at the illustration on the right, you can see colored borders on the black mark. The mark is printed with the passport color in each color of the color model. If there is a slight offset in the print, the colored marks do not appear completely covered by the black mark. So that this assessment of the registration difference is also possible with extended color models, the passport color must always contain all components. For example, in the extended color model CMYKOG, it contains cyan , magenta , yellow and black as well as orange and green .

In software

The color name All is used in the page description languages PostScript (from level 2) and PDF (from version 1.2) to make a representation of the passport color available that is independent of the color models of various output devices . It is a widespread mistake when using typesetting programs to change the registration color for normal elements that are to be displayed in black, e.g. B. Use continuous text .

Due to the special use for registration marks, the passport color is not printed with the appropriate setting by some common typesetting programs (e.g. FreeHand , Adobe InDesign ). This allows the registration marks to be hidden and makes the above-mentioned error recognizable.

Differentiation from bold black

The fit color should be mixed even with oily black ( english rich black ). Although it is also a black-appearing color with proportions of other color components, the composition (not 100%) and application are different.

Individual evidence

1. ^ Adobe Systems (Ed.): PostScript language reference . Addison-Wesley, Boston 1999, ISBN 0-201-37922-8 , pp. 243 ( adobe.com [PDF; 7.8 MB ]).