Xerox DocuColor 252 User Manual page 253

Glossary
PSImage
Quartertone
Raster file
Rasterization
Register
Register marks
Relative Colorimetric
Rendering Intent
A low-resolution EPS file used in the Creo APR workflow. This file is
used for positioning in page layout. Changes made to this file will be
applied to the high-resolution file, which automatically replaces it
shortly before exposure. See also APR.
The tone area of an image influencing highlight detail and with density
values between the white point and midtone. Typically, printed with a
dot area near 25%. See also Highlights, Midtones, Shadows.
A file of data that was scanned, processed or output sequentially, bit
by bit and line by line. Also known as a bitmap.
The translation of vector information into bitmap information. Bitmaps
may also require a new rasterization to comply with the screening
parameters (dot shape, dot size) of the imagesetter that will expose
them on film. See also RIP and RIPing.
Fitting of two or more printing images or plates in exact alignment with
each other.
Crosses or other targets applied to original copy prior to printing. Used
for positioning films in register or for register of two or more colors in
process printing.
A rendering intent method in which colors that fall within the output
color space remain the same. Only colors that fall outside are changed
to the closest possible color within the output color space.
When using this method, some closely related colors in the input color
space can be mapped to a single color in the output color space. This
reduces the number of colors in the image.
All printers, monitors and scanners have a gamut or range of colors
that they can output (or view in the case of a scanner). If a color needs
to be output and is outside the gamut of the output device, it must be
mapped or approximated to some other color, which exists within the
gamut. Rendering Intent enables you to compress out-of-gamut colors
into the color capability of the press you are using. You can set any
rendering intent value for RGB elements by selecting the required from
the Rendering intent options list. The default value for RGB is
Perceptual (photographic). The default value for CMYK is Relative
Colorimetric.
There are several methods that can be used when translating colors
from one color space to another. These methods are called Rendering
Intents because they are optimized for various uses. When working
with ICC profiles, it is important that you select the Rendering Intent
that best preserves the important aspects of the image. Each
rendering method specifies a CRD for color conversions. You can
modify the rendering method to control the appearance of images,
such as prints from office applications or RGB photographs from
Photoshop.
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