Maintenance And Inspection; Basic Image Adjustment Procedure - Canon NP6317 Service Manual

Image adjustment should be per-
formed using the following settings:
1. Manual (non AE) exposure
2. Density cursor setting : 5
3. DIRECT reproduction ratio
Pre-check
Clean the corona wires.
Make the following copies
(using test sheet NA-2 or
NB-3):
Copy density 5: 2 copies
Copy density 1: 1 copy
Check the following :
1. Differences in density
between the near and
far sides of the copies.
2. Density of gray scale
No. 10.
3. Fogging in blank areas.
Is the top
margin of the copy
YES
at copy density 1 within
the standard?
NO
Adjust Service mode ( ).
(See p. 2-1.)
Return copy density
to 5.
COPYRIGHT © 1999 CANON INC. CANON NP6317 REV.0 APR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)
Adjust the image by the following
procedure when the photosen-
sitive drum has been replaced.
Make this adjustment with the
upper front panel and front door
installed.
Adjusting side-to side
density
Is there a
difference in density
NO
on the near and far sides
of the copies?
YES
Is there a
difference in density
NO
in the image area of a
reduced copy?
YES
(Note 1)
Is the
distance bet-
ween the primary
Check for stains on the
corona grid and the photo-
scanning lamp, reflector
sensitive drum
plate, and mirror; clean
correct?
them if necessary.
NO
Replace the grid plate and
grid mounting panel.
Mount the drum unit
Make one copy.
and make one copy.
Adjusting the density
Is the
density of gray
scale No. 10 correct?
(See Note 3.)
Is the
density of gray
scale No. 10 too dark?
(See Note 3.)
Turn the copy density knob
clockwise. (Note 2)
YES
(The image will become
lighter.)
Replace the drum unit.
Make one copy.
Note 1 : The distance between the grid and
photosensitive drum is determined by
the spacer mounted on the grid.
Check for deterioration or damage to
the spacer.
Note 2 : This changes the developing bias, but
not the intensity of the scanning
lamp.
Figure 10-101
I. MAINTENANCE AND INSPECTION
A.

Basic Image Adjustment Procedure

YES
End.
NO
YES
NO
(See Note 4.)
Turn the copy density knob
counterclockwise. (Note 3)
(The image will become
darker.)
Note 3 : No. 10 on the gray scale of a copy
should reproduce the density of No. 8
on the gray scale of the test sheet,
and no fogging in the background
should be visible.
Note 4 : Turning the copy density knob clock-
wise too far past the proper position
will result in fogging in blank areas.
10-1