Ricoh LDD250, Service Manual

Page: 341 / 459

IMAGE PROCESSING
SM 6-19 C262/C265
Detailed
Des
cription
s
6.3.3 FILTERING
Types of Filters
•
MTF Filter
•
Adaptation Filter
•
Smoothing Filter
Filters for each Original Type
The type of filter that is used depends on the original type.
•
Letter mode: MTF Filter
•
Letter/Photo mode: Adaptation Filter
•
Photo mode: Smoothing Filter
•
Pencil mode: MTF Filter
•
Pale mode: Adaptation Filter
NOTE: The filters that are used for each mode can be changed. Please refer to
SP6-59-1~5 for details.
Features of the filters
MTF Filter:
•
When the filter is stronger in the main scan direction, lines parallel to the feed
direction are emphasized.
•
When the filter is stronger in the sub-scan direction, lines at right angles to the
feed direction are emphasized.
•
When the MTF filter is selected with SP6-59-1~5, the settings of SP6-6-1~10
(MTF Filter Setting) are used.
Adaptation Filter:
•
Lines are less clear, but small characters are clear.
Smoothing Filter:
•
Images are smooth, but text and lineart can become blurred.
6.3.4 MAIN SCAN MAGNIFICATION/REDUCTION
Changing the scanner speed enables reduction and enlargement in the sub-scan
direction. However, the ECU board handles reduction and enlargement in the main
scan direction. The processing for main scan magnification/reduction is the same
as in the previous digital machines.