Desktop Color, Continued
Image capture
The three types of image capture are line art, grey scale, and color.
LINE ART: Line art is images that are either black or white and have no
gradations in tone. Line art scanners record black as one bit and white as
one bit. This is called one-bit or bilevel scanning. Simulating halftones in
the scanned image is known as dithering.
GREY SCALE: Grey scale scanning is for continuous-tone art. The scanner
assigns grey levels based on the light that reflected from or passing through
the original image. Increasing bits per pixel (pixel depth) increases the
number of greys recorded and proportionally increases file size. Eight-bit
scanners produce 256 levels of grey.
COLOR: Desktop color scanners usually allow 8 bits per spectral primary
and 8 bits for black totaling 24 bits of information per pixel. This creates a
palette with more than 16 million available colors. Color monitors should be
capable of displaying 24 bit color. Convert images scanned as 24 bit color to
8 bits before displaying the image on monitors incapable of displaying 24 bit
color.
Color monitors
Color monitors display images and text while you work in the document.
The resolution and accuracy of a desktop system depends heavily on the
quality of monitor. Monitor resolution is defined by dpi (MAC) or pixels
(PC).
Screen size is measured diagonally across the monitor face. Large
monitors that display a full page or a two-page spread horizontally are ideal
for the DM and this type of monitor accuracy is often called WYSIWYG
(pronounced whizzywig), an acronym for What You See Is What You Get.
WYSIWYG monitors and appropriate software allow the DM to create and
correct art and copy with unparalleled accuracy. What you see on the
horizontally oriented screen is exactly what the hard copy should look like.
Vertically oriented monitors are called portrait monitors.
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