Epson Expression 1680 Reference Manual page 28

Note:
You can see the adjustments made by the Auto Exposure feature in the
Preview window. For details on using the Auto Exposure feature, see
"Auto Exposure" on page 2-37.
Dropout
Select a color to subtract from a black and white scan of a colored
original. Proper use of dropout can improve the quality of your
black and white scans. Available dropout options are:
None, Red, Green, and Blue.
Note:
Dropout is available only when Pixel Depth is set to 8-bit Gray or
Black & White.
Depending on the image, you may need to adjust the Threshold
setting in the Image Controls dialog box before making the Dropout
setting to achieve the desired effect. For more information on the
Threshold setting, see "Image Controls" on page 2-38.
B/W Options
These options are useful when scanning text or grayscale images.
Text Enhancement Technology
To improve recognition accuracy during OCR (optical character
recognition) scanning, select this option. This function eliminates
the document background from scans.
Auto Area Segmentation
To make grayscale images clearer and text recognition more
accurate, select this option. This function separates text from
graphics.
Note:
The B/W Option setting is available only when Black & White is
selected as the Pixel Depth setting.
2-8
Understanding EPSON TWAIN Pro Features