Epson PERFECTION 1240U Reference Manual page 71

De-screening:
Select either On or Off. When On is selected, moiré patterns are
automatically removed from scanned images, but scanning takes
longer.
Note:
❏ A moiré is a cross-hatch pattern that appears on scanned images
when scanning printed material. It is a result of interference that
occurs due to the difference between the pitches of the scanning and
the halftone screens.
❏ De-screening appears dimmed and is not available when Pixel Depth
is set to Black & White.
Color Smoothing
Select either On or Off. When On is selected, colors in an image
are related to limited number of index colors. This is useful when
scanning large areas of solid colors (for example, logos,
illustrations, and charts).
Note:
❏ The pixel depth of output image is 24-bit color.
❏ Color Smoothing is available only when Pixel Depth is set to 24-bit
color.
Auto Exposure Option:
Select either Photo or Document. You can see the effects of the
Auto Exposure Option setting in the Preview window when you
click the Auto Exposure button.
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.
Understanding EPSON TWAIN Features
3-11