This property sets the scan contrast. This property is only enabled when using a custom-built user interface (UserInterface=Suppress).
Property Value
From -1000 to 1000. The default value is 0
For Fujitsu PFU scan devices, when the PixelType property is Automation, GrayAndBW, or RGBAndBW, the value range for Contrast is from -127 to 127.
Explanation
The Contrast property sets the scan contrast. This property is only enabled when using a custom-built user interface (UserInterface=Suppress).
Note: There are cases when the PixelType property is BW and depending on the BitDepthReduction property value the Contrast property has no affect. See below.
The Contrast property is okay
When PixelType = BW and the BitDepthReduction = Halftone.
When the PixelType = Gray, RGB, or Palette
Note: This property is disabled for digital cameras and scanners that do not support these functions. The possible setting values supported by a scan device can be retrieved using the GetCapabilityEnumToSingle method or the GetCapabilityRange method.