Toshiba 451C Copier User Manual


 
e-STUDIO281c/351c/451c
2.6.1 To Adjust the Copy Image Quality in Black Mode
* You can start with any of the procedures. But it is recommended to perform the procedures in order, as listed
below. You can use one procedure in conjunction with another. But if this changes the image quality more
than required or loses effectiveness of the adjustment, restore the settings made in the previously used
procedure to the original. Then perform the next procedure.
* Procedure (1) is used by the service technician, and by the user.
* Procedures (2) to (4) are used by the service technician only.
(1) Press the [IMAGE] button on the Control Panel. Press the [BACKGROUND ADJUSTMENT] button.
Press the [LIGHT] button to decrease the background density.
After decreasing the background density, copy and check the image quality.
With the background density set to the minimum, if further image quality adjustments are still necessary, the
service technician must use the next procedure.
(2) Enter adjustment mode [05]. Change the values for codes [600 to 602] to adjust the background density.
Original
mode
[05] code Value recommended
Acceptable
value range
Default
Text/Photo 05-600
Text 05-601
Photo 05-602
Set a value smaller than 5. 1 to 9 5
* Set the value in increments of approximately 1, while checking the copy image until the optimum value is obtained.
After adjusting the background density, copy and check the copy image quality.
If further image quality adjustments are still necessary, use the next procedure.
(3) Enter adjustment mode [05]. Change the values for codes [590 to 592] to adjust the gamma curve balance
of the low- and medium-density areas.
Original
mode
[05] code Subcode Value recommended
Acceptable
value range
Default
Text/Photo 05-590 0/1
Text 05-591 0/1
Photo 05-592 0/1
Set a value smaller than 128. 0 to 255 128
* Set the value in increments of approximately 20, while checking the copy image until the optimum value is obtained.
* The subcode varies, according to the area for which the density is adjusted. Refer to the table below and
set the subcode for the area to be adjusted. The background density will vary, if the low- or medium-
density area is mainly adjusted. Setting "2" for the subcode allows you to adjust the high-density area.
But it will not affect the background density. Therefore, never change the values for the high-density area.
Subcode Area for the density to be adjusted
0 Low-density area
1 Medium-density area
After adjusting the gamma curve balance, copy and check the copy image quality.
If further image quality adjustments are still necessary, use the next procedure.
2. Copier-specific Adjustments
2.6