Epson Expression 1680 - Manual (Page 38)

2-18 Understanding EPSON TWAIN Pro Features
Fast Preview
Enables high-speed loading of the previewed image. If this is
selected, the document is scanned quickly at draft quality. If this
is not selected, the previewed image is scanned at a high quality,
and you can get accurate values for the Highlight, Shadow, and
Gray Balance Intensity by sampling with the eyedropper in the
previewed image.
Do not select this setting when quality is more important than
speed.
Eyedropper Sampling Area
This setting allows you to specify the area in pixels that is sampled
when using the eyedropper to make the Highlight, Shadow, and
Gray Balance Intensity settings. You can choose from the
following settings:
1 x 1 pixel , 3 x 3 pixels , and 5 x 5 pixels .
Note:
If you select the
3 x 3 pixels or 5 x 5 pixels setting, an average of the
color values of the sampled pixels is used when adjusting the Highlight,
Shadow, or Gray Balance setting.