Canon imageRUNNER ADVANCE C255 Series, Service Manual, Page: 647 / 987

■ V-CONT
COPIER (Service mode for copier) > ADJUST (Adjustment mode) > V-CONT
VCONT-Y 2 Adj of Y-color contrast potential
Detail To adjust the contrast potential for Y.
As the value is incremented by 1, the contrast potential changes by 10V.
+: Image becomes darker.
-: Image becomes lighter.
When the value is too large, paper winds around the Fixing Roller or a transfer failure occurs.
In a low humidity environment (e.g. winter in North America or Japan), the output may not be
changed by increasing the value.
In principle, the adjustment of the density should be performed in Adjustment/Maintenance> Adjust
Image Quality> Density Adjustment Mode.
Use Case When adjusting the density of D-max control in the case that an image density failure occurs
Adj/Set/Operate Method 1) Enter the setting value (switch negative/positive by -/+ key) and press OK key.
2) Execute Auto Adjust Gradation> Full Adjust.
Caution Do not use this when the machine is operating correctly.
Display/Adj/Set Range -5 to 5
Unit V
Default Value 0
Related Service Mode COPIER> ADJUST> V-CONT> VCONT-M/C/K
Additional Functions
Mode
Adjustment/Maintenance> Adjust Image Quality> Auto Adjust Gradation> Full Adjust
Adjustment/Maintenance> Adjust Image Quality> Density Adjustment Mode
Amount of Change per
Unit
10
VCONT-M 2 Adj of M-color contrast potential
Detail To adjust the contrast potential for M.
As the value is incremented by 1, the contrast potential changes by 10V.
+: Image becomes darker.
-: Image becomes lighter.
When the value is too large, paper winds around the Fixing Roller or a transfer failure occurs.
In a low humidity environment (e.g. winter in North America or Japan), the output may not be
changed by increasing the value.
In principle, the adjustment of the density should be performed in Adjustment/Maintenance> Adjust
Image Quality> Density Adjustment Mode.
Use Case When adjusting the density of D-max control in the case that an image density failure occurs
Adj/Set/Operate Method 1) Enter the setting value (switch negative/positive by -/+ key) and press OK key.
2) Execute Auto Adjust Gradation> Full Adjust.
Caution Do not use this when the machine is operating correctly.
Display/Adj/Set Range -5 to 5
Unit V
Default Value 0
Related Service Mode COPIER> ADJUST> V-CONT> VCONT-Y/C/K
Additional Functions
Mode
Adjustment/Maintenance> Adjust Image Quality> Auto Adjust Gradation> Full Adjust
Adjustment/Maintenance> Adjust Image Quality> Density Adjustment Mode
Amount of Change per
Unit
10
8. Service Mode
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