Xerox 242 - Manual (Page 252)

244 Spire CX260 User Guide
OPI Abbreviation of Open Prepress Interface. A prepress convention
established by Aldus Corps. OPI refers to tags or place holders in
source PostScript that point to TIFF or EPS images that have not been
embedded in the PostScript. These images reside in other locations
and are merged with the PostScript file when processed. Normally
used for performing high res/low res image substitution (alternative
to Creo APR).
Output resolution The number of laser dots per unit of linear measurement (millimeter,
inch etc.) on film or paper.
Output tone curve A graph showing the relationship of original input densities and the
corresponding dot percentages on film.
Overprint A technique, which overlaps colored elements to eliminate the
appearance of gaps between elements caused by misregistration of
the various separations during printing. For example, black text is
normally set to overprint. See also
Trapping and Misregistration.
PDL Printer Description Language files (for example, PostScript, PDF, EPS,
VPS, VIPP). The Spire CX260 processes image files in PDL formats,
converting them into a suitable Ready-To-Print format for direct, high-
quality printing.
Perceptual (Photographic) (Default for RGB) A rendering intent method which preserves the
visual relationship among the colors as they are perceived by the
human eye. In other words, all colors are proportionally scaled to fit
the output gamut. All or most colors in the original are changed but the
relationship between them does not change.
This method is recommended when working with realistic images
such as photographs, including scans and images from stock
photography CDs.
PICT A Macintosh file format for bitmaps and vector graphics.
Pixels Contraction of Picture Element. The smallest element of a digital
image.
PostScript A programming and page description language that has become
industry standard for electronic publishing. It is used to describe the
entire page, including both text graphics and images. PostScript is
completely independent of the printing device. Developed by Adobe
Systems, Inc.™
Prepress Generic term used to describe the processes involved in preparing
images for printing. Includes the input, edit and output stages.
Printer description files PPDs (PostScript Printer Definition), and PDFs (Printer Definition
Files). These files are used by the Macintosh applications to prepare
page and documents for specific output devices.
Process colors The four ink colors used to reproduce full color images - cyan,
magenta, yellow and black.