Fuji Xerox ApeosPort-IV C7780 Administrator's Manual page 639

Making adjustment using [Enter Percentage]
If you are familiar with adjusting the transfer output value, you can specify the value
without printing a sample printout.
1) Select [Enter Percentage], and specify the adjustment value (percentage) for [Side
1] and [Side 2]. The current output value is assumed to be 100%.
Increase the percentage value if image transfer is still poor.
2) Press [Adjust].
The transfer output value set here will be applied to subsequent printouts.
10
Press [Close].
Adjust Image Transfer
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