Ricoh A250 Service Manual page 74

IMAGE PROCESSING
Smoothing Filter Adjustment - Photo Mode
Image adjustment (08) in the user tools
Mode
Text
Text/Photo
Photo
When the user selects "Service Mode" for Photo original type (User Tools - General
Features - 08. Image Adjustment), the smoothing filter can be changed with SP4-
927. A stronger smoothing filter makes the image more blurred (1: Weak ~ 8:
Strong).
Smoothing Filter Adjustment - Text and Text/Photo Modes
To reduce the possibility of moiré, a small-matrix smoothing filter is used after
scanner gamma (γ) correction in the Text and Text/Photo mode. The level of
smoothing can be adjusted with SP4-921 (0: Weak, 1: Normal, 2: Strong, 3:
Disabled).
This is only used when the user selects "Service Mode" for either Text or
Text/Photo original type (User Tools - General Features - 08. Image Adjustment).
Independent Dot Erase
In Text mode and in Text/Photo mode, independent dots are detected using a 7 x 9
matrix and erased from the image.
The independent dot detection level can be adjusted with SP4-917 (for the original
modes known as "Service Mode") and SP4-944 (other original modes – on/off only;
no adjustment). With a larger SP setting, more dots are detected as independent
dots and erased, even if the dot's density is high. However, dots in mesh-like
images may be detected as independent dots mistakenly.
Independent Dot Erase after Binary Picture Processing
Image adjustment (08) in the user tools
Mode
Text
Text/Photo
Photo
Normally, independent dot erase is done in the filtering stage. However, when the
user selects "Service Mode" for Text original type (User Tools - General Features -
08. Image Adjustment), independent dots may reappear in the image after the
binary picture processing. These independent dots are erased after gradation
processing.
SP4-939 changes the filter that is used for this process, and it can be also used to
disable this feature. A smaller matrix is more likely to remove dots.
A250
Toner Saving
— Photo Priority
Coarse Press Print
Toner Saving
— Photo Priority
Coarse Press Print
Default
Normal Sharp
Text Priority
Glossy Print
Default
Normal Sharp
Text Priority
Glossy Print
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(Service Mode)
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