Uneven Density or Mottle
Problem
Uneven Density or Mottle
Solutions
1. Perform Adjust Image Transfer.
• Use this feature to adjust the voltage ratio on the secondary bias transfer roll (2nd BTR). For heavy-weight paper, such as 220 g/m2 or greater, the 2nd BTR is where the image is transferred from the belt to the paper. However, there are times when it is also used with lightweight paper.
• This feature is accessed from > > > . Select the desired > > > .
• The Adjust Image Transfer procedure can be performed by selecting Auto or Manual.
Note: An automatic adjustment fixes most image quality issues. Always perform the Auto procedure before performing the Manual adjustment.
▪ Auto: The adjustment is done automatically by the press. It eliminates the need for you to interpret printed targets and manually enter adjustment values. This saves time and avoids errors.
▪ Manual: The user must manually perform the adjustment, including printing test patterns, interpreting the printed targets on those patterns, then manually entering the adjustment values.
Tip:
Use the Manual adjustment option only when the Auto adjustment does not provide the desired output.
▪ For detailed information and instructions on how to use the Auto and Manual adjustment options, refer to the System Administrator Guide.
2. If the issue is observed on the tail edge of the printed output and is not corrected by performing a Adjust Image Transfer, change the Adjust Image Transfer for Trail Edge setting.
• Use this feature to adjust the voltage ratio on the secondary bias transfer roll (2nd BTR); this is where the image is transferred from the belt to the paper.
• This feature is accessed from > > > . Select the desired > > > .
• Decrease the Adjust Image Transfer for Trail Edge in increments of 10%. After every incremental adjustment, run test prints and evaluate the output to determine if additional adjustment is necessary.
3. Perform an Automatic Density Uniformity Adjustment.
Note: This is a press feature and is not a Custom Paper Settings feature.
• Use this feature to correct image quality issues on the output when that image quality is not consistent throughout the entire output. For example, the image quality is lighter (faded) or heavier (thicker) on the left or right sides of the output (inboard / outboard).
• For information and instructions on how to use this feature, refer to the System Administrator Guide.