Image Quality Adjustment (Copying Function) - Toshiba e-STUDIO 2555C Service Manual

6.2

Image Quality Adjustment (Copying Function)

6.2.1 Automatic gamma adjustment
When the reproduction of gradation is not appropriate, the gradation reproducibility of all colors Y, M, C
and K can be corrected by performing this automatic gamma adjustment. In case the gradation
reproduction of the image checked is not satisfactory, make this adjustment as described below at parts
replacement.
(1) When unpacking or any of the following parts has been replaced, be sure to make this
adjustment:
• Photoconductive drum
• Developer material
• LED head
• LED gap spacer
• Transfer belt
• 1st transfer roller
• Drum cleaning blade
• Needle electrode
• Main charger grid
• Image position aligning sensor (Front)
• Image position aligning sensor (Rear)/Image quality sensor
• SRAM board (SYS board)
• EEPROM (LGC board)
• HDD
(2) When any of the following parts are replaced or adjusted, make a copy and check the image to
determine if adjustment is necessary:
• 2nd transfer roller
Notes:
Be sure that this adjustment be made after performing the image adjustment in  P. 6-4 "6.1.3
Performing Image Quality Control" and  P. 6-6 "6.1.5 Image Dimensional Adjustment".
<Procedure>
While pressing [0] and [5] simultaneously, turn the power ON. → Adjustment Mode
(1)
(2) Select the A4/LT/A3/LD drawer. Key in the pattern number and press the [FAX] button to output a
"Patch chart for gamma adjustment".
<Adjustment Mode (05)>
Pattern No. Pattern No.
4 Color/black integrated
200 Color/black integrated
204 Color/black integrated
206 Color/black integrated
208 Color/black integrated
210 Color/black integrated
212 Color/black integrated
214 Color/black integrated
216 Color/black integrated
218 Color/black integrated
220 Color/black integrated
© 2012-2013 TOSHIBA TEC CORPORATION All rights reserved
Remark
When performing code 05-7869
When performing code 05-7871-0
When performing code 05-7871-2
When performing code 05-7871-3
When performing code 05-7871-4
When performing code 05-7871-5
When performing code 05-7871-6
When performing code 05-7871-7
When performing code 05-7871-8
When performing code 05-7871-9
When performing code 05-7871-10
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e-STUDIO2555C/3055C/3555C/4555C/5055C
SETTING / ADJUSTMENT
6