Printer Gamma Adjustment - Konica Minolta 8050 Service Manual

KONICA MINOLTA 8050/CF5001/C500/8150 Field Service Ver.3.0 Dec. 2004
13. When the gray balance is not the same, press
the key of a color (Y or M) you want to adjust,
enter a numeric value through the numeric
keys and press the [SET] key.
• Setting range: -128 (lighter) to +127 (darker)
Note:
• There are three keys: [1/1], [1/2] and [1/3]
provided for each line speed. Be sure to use
the key [1/1] for adjustment. A value entered
by the key [1/1] is automatically inputted into
keys [1/2] and [1/3].
• How to match the gray balance
Take notice of the gray patches [4] made up of
49 colors of C, M and Y. In the 49 patches, M
gets darker as going right to left. And Y gets
darker as going down from up. However, C is
fixed. The patch [5] at the center is the same
color as the gray [2]. The patches [6] positioned
at the four corners of the patch [5] is the same
color as the gray [3]. Out of the 49 patches,
select a gray of the same gray balance as the
gray [6].
e.g.) When a patch on the lower right side is
more suitable than the patch [5] at the center:
Adjust M and Y in the positive direction.
When a patch on the upper left side is more
suitable than the patch [5] at the center: Adjust
M and Y in the negative direction.
14. Press the [COPY SCREEN] key.
15. Set A4 or 8.5 x 11 paper in the bypass tray and
press the START button to print a test pattern.
16. Repeat steps 13 to 15 until you can get a satis-
factory result.
17. Press the [PREVIOUS SCREEN] key to return
to the "Printer gamma adjustment menu
screen."
(2) Printer gamma sensor adjustment
When a poor color reproduction results even after
the automatic gamma adjustment of the process
adjustment, conduct this adjustment to correct gra-
dation.
The printer gamma correction that is carried out
automatically and periodically uses a gamma sen-
sor to read patterns on the transfer belt. So, there is
a possibility of the gamma sensor not being accu-
rately adjusted due to the change in characteristic
of the gamma sensor. This adjustment use the
scanner to correct the gamma sensor for accurate

printer gamma adjustment.

This adjustment can be shown in the key operator
mode by setting the DIPSW12-1 to 1.
a. Procedure
1. Enter the 36 mode.
2. "36 mode menu screen"
Press the [3. Image quality adjustment] key.
3. "Image quality mode menu screen"
Press the [2. Printer gamma adjustment] key.
4. "Printer gamma adjustment menu screen"
Press the [2. Printer gamma sensor adj.] key.
1-85
36 MODE
2