Ricoh MP C6502SP System Maintenance page 177

Front Side
001
Corrects color for low chroma area of front side.
With 1 path duplex model, color might change between front/Rear sides due to scanning
format difference.
If user points out this difference, with changing this setting, difference can be reduce.
Adjust intensity by color difference.
As a side effect, low chroma area's reproducibility will spoil as stronger the intensity gets.
Rear Side
002
Corrects color for low chroma area of rear side.
With 1 path duplex model, Color might change between front/Rear sides due to scanning
format difference.
If user points out this difference, with changing this setting, difference can be reduce.
Adjust intensity by Color difference.
As a side effect, low chroma area's reproducibility will spoil as stronger the intensity gets.
4797 [Rear Side: Digital AE]
Low Limit Value
001
Sets Lowest threshold to detect as background when DF rear side-scanning.
Decides area of input image data brighter (larger value) then threshold.
Background Erase Level
002
Sets background level to decide output value for background erase when DF rear side
scanning.
[0 to 3 / 0 / 1/step]
0: No color correction for low chrome
area(Default)
*ENG
1: Correct low chroma area(weak)
2: Correct low chroma area(medium)
3: Correct low chroma area(strong)
[0 to 3 / 0 / 1/step]
0: No color correction for low chroma
area(Default)
*ENG
1: Correct low chroma area(weak)
2: Correct low chroma area(medium)
3: Correct low chroma area(strong)
*ENG [0 to 1023 / 364 / 1/step]
*ENG [512 to 1535 / 932 / 1/step]
SP4-XXX (Scanner)
175