166
BOOK TOC
CHAPTER TOC
SEARCH
PREVIOUS PAGE
NEXT PAGE
SCANNER CONTROL TABS
It actually provides 256 shades, representing white by the value 255 and
black by the value zero, with progressively lighter intermediate shades of
gray by values from 1 through 254.
Halftone B/W
This scan mode uses various combinations of black and white pixels to
simulate gray scales. While not the same level of image quality as the Gray
256 Scales image type, this image type is good for continuous tone images
where smaller file size is more important than ideal image quality.
In this scan mode, each pixel of the image has two possible states: on (black)
or off (white). This means that each pixel can be represented by 1 bit. For
this reason, the file size is much smaller than that of a document scanned in
the Gray 256 Scales mode, which uses 8 bits to define 256 shades of gray.
Lineart B/W
Lineart B/W mode is generally the best choice for printed text or pen-and-ink
drawings.
Like the Halftone B/W image type, this image type defines the state of each
pixel in the image with one bit that is either on or off.
For this reason, files created in this mode will require approximately the
same amount of disk space as a Halftone B/W file.
Note: In both Halftone and Lineart modes, the resolution can only be set at
150, 200, or 300 dpi.
