Leica DFC Series Manual page 49

You can also set the separate red, green and blue
values by right-clicking Check Color and selecting Set
Color Values which will open the following panel:
The Color Wheel can freely float anywhere in the
screen area while DFC Twain is active.
On the Live Image:  Adjust the ROI for color fine-tuning by drawing a
rectangle in the live image and select Check Color .
Measuring area for color fine-tuning
51
Leica DFC Cameras – Image Acquisition Guide