Glossary of pre-press, R. Raster RIP, resolution, reflective.

Glossary of pre-press, graphic arts and color reproduction terminology beginning with the letter R.

Raster image processor (RIP)

A RIP is a hardware or software tool that processes a digital PostScript file and converts it - rasterises - to a printable format.

See also: PostScript

Rasterize

Rasterizing (or rasterising) a graphic is to convert it from vector data to bitmap pixels. Adobe Photoshop will rasterize an image when it opens an EPS file from Illustrator, for example.

Reflective

The opposite of a transparency or transmissive, in that it reflects light. A photograph is a typical reflective artwork.

Registration marks

Register marks, or registration marks, are thin lines – generally cross-hair patterns – which are printed in all colors on an unfinished document. This allows the printer to accurately register all the printing plates and ensure accuracy and sharpness.

In desktop publishing software packages, such as QuarkXpress and InDesign, there is an undeleteable color called the registration color, which appears black as it consists of 100% of all printing inks.

Resolution

For the sake of graphics reproduction, the resolution of a bitmap digital graphics image is a measure of its quality, or the amount of digital information it contains. Resolution is measured by the amount of pixels an image contains in height and width. For professional printed reproduction, the resolution of a bitmap graphics file must be between 1.5 and 2.5 times the resolution of the line screen.

Also worth reading about is a discussion on the various forms of digital image resolution when used for different purposes, such as in print versus web design. The discussion difference between dots per inch, pixels per inch & halftone screens covers the basics of this confusing topic.

Rich black

Because of impurities in commercial printing inks 100% solid black generally appears nearer to a dark gray. Because of this, printers often add a 'wash' of other coloured inks to create a rich black. Typically this is 40% of cyan, but other combinations of cyan, yellow, magenta and black are not unknown.