Canon iR6570 series, Portable Manual

Page: 40 / 320

Chapter 2
2-6
F-2-5
2.1.4 Making Checks on the Reader Unit
0008-7912
iR5570 / iR6570
F-2-6
<Checking the Halftone Density>
Generate a halftone image.
End.
To check a copier image,
See if No. 6 and No. 7 (halftone) of the Test Chart is
reproduced to the more or less the same density.
To check a printer (PDL) image,
See if the density of the halftone area represents the
original data properly.
Is the halftone
density optimum?
NO
YES
Adjusting the Offset Value of the VD Target Potential
(VD-OFFSET/VD-OFFSET-P)
COPIER>ADJUST>V-CONT>VD-OFST (for copier image)
COPIER>ADJUST>V-CONT>VD-VD-OFST-P (for printer image)
Default
Lighter image Darker image
-5 -4 -3 -2 -1 0 +1 +2 +3 +4 +5
C
D
Is there a difference
in density between
front and rear?
Are there vertical
lines in the images?
Clean the following:
1. Mirrors
2. Lens
3. Standard white plate
(mounted to back of
copyboard glass)
4. Copyboard glass
< Making Image Initial Checks> <Checking the Density Slope>
YES
YES
NO
NO
NO
YES
Perform the instructions under
“”for the printer unit.
Is there a
difference in density
between front
and rear?
Execute shading in service mode:
COPIER>FUNCTION>CCD>CCD-ADJ
Execute shading in service mode:
COPIER>FUNCTION>CCD>CCD-ADJ
Clean the mirrors.
E