Output Options - Epson Expression 1680 Reference Manual

Note:
The Tone Correction button is unavailable when one or more
marquees are selected in addition to the active marquee.
The Linear setting is the default Tone Correction setting.
The Tone Correction feature is not available when Pixel Depth is set
to Black & White, Halftone is set to None, and Text Enhancement
Technology is selected in the Image Type dialog box.
To save your Tone Correction settings, type a new name in the
Tone Curve Name box and click Save. To delete a setting from
the Tone Curve Name list, select the setting and click Delete.
To apply your Tone Correction settings, click OK. To restore the
original settings, click Cancel.
For further information on using Tone Correction to optimize
scanning, see "Making tone curve settings" on page 1-9.
Tone Curve editor
The editor allows you to customize tone correction. Drag points
on the tone curve to adjust the tone value. You can edit up to five
tonal elements.

Output options

If you select the check box for a specific point, such as 1/4 Tone
or Midtone, you can move that point and it will remain where you
leave it; it will not be affected by the movement of other points on
the curve. If the check box is cleared, the point will be affected by
the movement of other points.
Channels options
You can select the combined red, green, and blue (RGB) channel
to modify all colors, or select each of these colors separately.
Understanding EPSON TWAIN Pro Features
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