Honeywell 1900GHD-2 User Guide - Page 210

W - Target White Value Sets the target for the median grayscale value in the captured image. For capturing close-up images of high contrast documents, a lower setting, such as 75, is recommended. Higher settings result in longer exposure times and brighter images, but if the setting is too high, the image may be overexposed. Target White Value is only available when using Photo Style (1P). (Default = 125) nW Range: 0 - 255 Example of White Value at 75W: Example of White Value at 125W: Example of White Value at 200W: D - Delta for Acceptance This sets the allowable range for the white value setting (see W - Target White Value). Delta is only available when using Photo Style (1P). (Default = 25) nD Range: 0 - 255 U - Update Tries This sets the maximum number of frames the scanner should take to reach the D - Delta for Acceptance. Update Tries is only available when using Photo Style (1P). (Default = 6) nU Range: 0 - 10 % - Target Set Point Percentage Sets the target point for the light and dark values in the captured image. A setting of 75% means 75% of the pixels are at or below the target white value, and 25% of the pixels are above the target white value. Altering this setting from the default is not recommended under normal circumstances. To alter grayscale values, W - Target White Value should be used. (Default = 50) n% Range: 1 - 99 Example of Target Set Point Percentage at 97%: Example of Target Set Point Percentage at 50%: Example of Target Set Point Percentage at 40%: 8 - 4