Epson Expression 1680 Reference Manual page 41

If your printer and monitor do not support the available color
management system, select Color Controls. See your printer and
monitor documentation to check if they support ICM or ColorSync.
When ICM or ColorSync is selected, the Continuous Auto
Exposure setting is unavailable.
If ICM or ColorSync is selected, whenever the Auto Exposure
function is used, the Shadow setting in the Image Controls dialog
box is automatically set to 8, and the Gamma setting is set to 1.0.
ICM is not available in Windows NT 4.0.
In Windows 95, you can select the ICM setting, but the Source
(Scanner) and the Target settings are not available.
If you select ICM or ColorSync in EPSON TWAIN Pro when using
Adobe Photoshop 5.0 or 5.5, be sure to clear the Display Using
Monitor Compensation check box in Photoshop's RGB Setup
Dialog box.
Source (Scanner)
Choose a color profile for the scanner you are using from this list
box. EPSON recommends selecting EPSON Standard when using
an EPSON scanner.
Note:
This setting is not available in Windows 95 and NT 4.0.
Target
In this list box you can choose a color profile that matches either
your monitor or an other output device, such as your printer, or
you can choose one of the RGB color space profiles that matches
those available in Adobe Photoshop.
Understanding EPSON TWAIN Pro Features
2-21