Ricoh A-C4, Руководство по обслуживанию

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IMAGE PROCESSING 20 June 2005
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SP4904 4 Density Setting for Copied Original Mode
Settings Density Characteristics
0 Selects normal density (Default) for Generation Copy originals.
1 Produces better gradation in fill areas of high density.
If “1” is selected for SP4904, the following SP mode settings may also need
adjustment.
SP No. Function Recommended Setting
SP4903 57 Filter Level: Generation Copy 4 (or change as required)
SP4903 58 Filter Strength: Generation Copy 2 (or change as required)
SP4903 64 Independent Dot Erase: Generation Copy 0 (OFF)
SP4903 69 Background Erase Level: Generation Copy 0 OFF
SP4903 75 Line Width Correction: Generation Mode 0 (LWC OFF)
ADS Level
This section shows you how to adjust the center notch for the ADS (Automatic
Density Setting) level. The notches are not displayed during ADS adjustment. Of 7
steps (notches) the center notch is 4. This is the value adjusted with this SP code.
SP5106 6 (ADS Level Selection) selects the image density used in ADS mode. For
example, if you set SP5106 66 to “2”, pressing the Auto Image Density key toggles
the display off and manual notch 2 is selected. This SP code is adjusted, if the
customer cannot attain clean copies after performing automatic density adjustment.
This mode prevents the background of an original from appearing on copies.
The copier scans the auto image density detection area, a narrow strip at one end
of the main scan line. As the scanner scans down the page, the IPU on the BICU
detects the peak white level for each scan line in this narrow strip only. The IPU
uses this peak white level as a reference value for analog-to-digital conversion of
the scan line, then the IPU sends the reference value to the A/D controller on the
SBU.
When an original with a gray background is scanned, for example, the density of
the gray area becomes the peak white level density, so the original background will
not appear on copies. Because peak level data is taken for each scan line, ADS
corrects for any changes in background density down the page.
As with previous digital copiers, the user can select manual image density when
selecting auto image density mode and the machine will use both settings when
processing the original.