Xerox CX PRINT SERVER 560 - Manual (Page 110)

Parameter Option Description
PostScript
overprint Uses the overprint information that exists in the PostScript
file. This option also determines whether the DTP
application's PostScript overprint settings are retained in
the RIP.
Screening Screening Converts images, graphics and text into information that
can be printed (halftone dots). The human eye “smoothes
out” this information, which seems visually consistent with
the original picture. Thus, the more lines per inch, the more
natural the image appears. Screening is achieved by
printing dots in numerous shapes or lines in an evenly
spaced pattern. The distance between the screen dots or
lines determines the quality of the image. Printers can work
with constant amounts of toner and still produce a wide
range of colors when you use screening. The darker the
color, the larger the dot.
To print an image on a digital printer or press, the color
server needs to digitally approximate the grayscale values
with different distributions of pixels. This process is
commonly referred to as halftoning. Digital halftoning
begins by sampling the original image at the same number
of dots per inch as the printer and constructing digital
halftone cells.
100 Chapter 11—Job parameters