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MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 28

Color copy check items (Check to confirm the following:)
1) There are 12 void areas.
2) Registrations (one point for the main scanning, and one point

for the sub scanning) are not shifted.

3) The resolution of 5.0 (5 points) can be seen.

4)

The color difference in gray balance between the F and the R
sides is not so great.

5)

There are no white and black streaks.

6)

Color texts are clearly reproduced.

7)

The background density is not so light.

Color difference in gray balance between the F and the R sides
No white and black streaks

Background density

Color text reproduction capability

Void

Void

Void

Void

Void

Void

Registration

Resolution

Resolution

Resolution

Resolution

Resolution

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 29

Monochrome copy check items (Check to confirm the following:)
1) There are 12 void areas.
2) The resolution of 4.0 (5 points) can be seen.
3) The density difference between the F and the R sides is not so

great.

4)

There are no white and black streaks.

5)

The background density is not so light.

6)

The black low-density gradation is copied slightly.

Void

Resolution

Void

Low-density gradation

Resolution

Density difference between the F and the R sides.
No white and black streaks

Background density

Resolution

Resolution

Void

Void

Void

Void

Resolution

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 30

Method 2
Use SIM46-21 to print the color balance adjustment sheet, and
check each process (CMY) black patch color balance and the black
patch in order to confirm that the color balance adjustment is
proper or not more precisely.

If the color balance of each patch of the process black (CMY mixed
color) is slightly shifted to Magenta, it means that the adjustment is
proper. If the color balance of the adjustment pattern printed in this
mode is slightly shifted to Magenta, it is converted into the natural
gray color balance by the color table in an actual copy mode.
(When the color balance target is DEF 1.)

CAUTION: Before checking the copy color balance and the density,

be sure to execute the following procedures in advance.

* Execute the high density image correction (Process correction)

forcibly. (SIM 44-6)

* The half-tone image correction is forcibly executed. (SIM 44-26)

Method 1
Execute SIM 64-5 to print the print test pattern.

Set each set value to the default and press [EXECUTE] key. The
print test pattern is printed.

The print density must be changed gradually from the lighter level
to the darker level. The density changing direction must not be
reversed. The density level of each color must be almost at the
same level.

Method 2
Use SIM 67-25 to print the color balance adjustment sheet and
compare each process (CMY) black patch color balance and the
black patch to check the color balance.

The print density must be changed gradually from the lighter level
to the darker level. The density changing direction must not be
reversed.
The density level of each color must be almost at the same level.
Patch B may not be copied.
Patch A must not be copied.
If the color balance of each patch of the process black (CMY mixed
color) is slightly shifted to Magenta, it means that the adjustment is
proper. In an actual print mode, it is converted into the natural gray
color balance by the color table. (When the color balance target is
DEF 1.)

 

This adjustment must be performed in the following cases:
* When the CCD unit is replaced.
* When a U2 trouble is occurred.
* When the scanner control PWB is replaced.
* When the EEPROM on the scanner control PWB is replaced.

(1) Note before adjustment
-  Check that the table glass, No. 1, 2, 3 mirrors, and the lens sur-

face are free from dirt and dust. 
(If there is some dust and dirt, wipe and clean with alcohol.)

-  Check to confirm that the patches in BK1 and BK2 arrays of the

SIT chart (UKOG-0280FCZZ or UKOG-0280FCZ1) are free from
dirt and scratches.
If they are dirty, clean them.
If they are scratched or streaked, replace with new one.

Q

O P

N

M

L

K

J

I

H

G

F

E

D

C

B

A

Y

M

C

Bk

High 
density

1) The max. density section is not blurred.

2) Patch C or D of each of Y, M, C, and BK is very slightly copied.

Low 
density

CMY
blend

3) Patch for each of Y, M, C, BK

The patch density is identical between patches or not reversed.
The patch density is changed gradually.

Q

O P

N

M

L

K

J

I

H

G

F

E

D

C

B

A

Y

M

C

Bk

1) The max. density section is not blurred.

2) Patch C or D of each of Y, M, C, and BK is very slightly copied.

Low density

CMY
blend

3) Patch for each of Y, M, C, BK

The patch density is identical between patches or not reversed.
The patch density is changed gradually.

High density

MX-7500N  ADJUSTMENTS AND SETTINGS  5 – 31

(2) Adjustment procedures
1) Set the SIT chart (UKOG-0280FCZZ or UKOG-0280FCZ1) to

the reference position on the left rear frame side of the docu-
ment table.
Set the chart so that the lighter density side of the patch is on
the left side.

If the SIT chart is not available, execute SIM 63-5 to set the
CCD gamma to the default. In this case, however, the adjust-
ment accuracy is lower when compared with the adjustment
method using the SIT chart.

CAUTION: Check to insure that the SIT chart (UKOG-0280FCZZ or

UKOG-0280FCZ1) is in close contact with the docu-
ment table.

NOTE: UKOG-0280FCZZ is equivalent to UKOG-0280FCZ1.
2) Enter the SIM 63-3 mode and press [EXECUTE] key.

The automatic operation is started. During the adjustment,
[EXECUTE] is highlighted. After completion of the adjustment,
[EXECUTE] returns to the normal display.

NOTE: Since the SIT chart (UKOG-0280FCZZ or UKOG-0280FC

Z1) is easily discolored by sunlight (especially ultraviolet
rays) and humidity and temperature, put it in a bag (such
as a dark file) and store in a dark place of low temperature
and low humidity.

a. General
When the automatic color balance adjustment is executed, a cer-
tain color balance (gamma) is used as the target.
There are following three kinds of the target.
-  Factory color balance (gamma) target
-  Service color balance (gamma) target
-  User color balance (gamma) target
In the above three, only the service color balance target can be set
to a desired level.
This setting is required in the following cases.
* When the color balance and density adjustments are executed

manually (SIM46-21) (SIM67-25)

* U2 trouble has occurred.
* When the MFP PWB is replaced.
* When the EEPROM on the MFP PWB is replaced.
* The scanner control PWB has been replaced.
* The EEPROM on the scanner control PWB has been replaced.
* When the user requests for customizing the color balance.
* When the service color balance target gamma is judged as

improper.

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A

Factory color 
balance (gamma) 
target

There are three kinds of the color balance target, 
and each of them is specified according to the 
machine design. Use SIM 63-11 to select one of 
them as the factory target. The default setting 
(factory setting) is the color balance (DEF1) 
which emphasizes color reproduction.

B

Service color 
balance (gamma) 
target

This target is used when the user requests to 
customize the color balance to user's desired 
level. In advance, the user's unique color 
balance must be registered as the service color 
balance target. The above registration (setting) 
is made by the serviceman with SIM 46-21 to 
adjust the color balance and with SIM 63-7 to 
register it.
This color balance target is used when the user 
executes the color balance adjustment. When, 
therefore, the service color balance target is 
changed, the color balance target of the user's 
color balance adjustment is also changed. 
When, however, SIM 63-8 is executed, the color 
balance is set to the factory color balance target 
set with SIM 63-11. The default setting (factory 
setting) of the color balance is same as the 
factory color balance target. (Emphasized on 
color reproduction (DEF1)) 
If the user does not request for customizing the 
color balance, be sure to use SIM 63-8 to set the 
color balance to the factory color balance target.

C

User color 
balance (gamma) 
target

Same color balance as the service color balance 
(gamma) target When the service color balance 
target is changed, this color balance target is 
also changed accordingly.