Epson Expression 1680 - Manual (Page 10)

1-2 Optimizing Scanning
6. Manually adjust the tone curve for individual colors in the
Tone Correction dialog box. See “Making tone curve settings”
on page 1-9.
Adjusting Brightness and Contrast
Adjust brightness and contrast before adjusting image color.
Brightness and contrast settings should be made in the order they
appear in this section.
Making the Highlight setting
Highlights are the brightest areas of an image. Follow these steps
to adjust the Highlight setting.
1. Click the Image Controls button in the Preview window.
2. Click the eyedropper button under Highlight.