GRASS VALLEY EDIUS VERSION 5.1 User Reference Manual page 547

Creating Video Composites
Figure 636. Chromakey Color Block Color Selector
Autofit Button
Click the button to automatically define keyer settings appropriate
Autofit
for the selected key color.
Detail Button
The Detail button shows detailed keyer settings which can be modified to
fine tune the key color parameters. These settings vary based on the color
selector method.
Figure 637 Shows the Detail Settings for the Color Wheel Selector.
Figure 637. Chromakey Color Wheel Selector Detail
Rectangle
Selecting the "Rectangle enable" option allows chromakey settings to be
applied to a selected rectangular area of the video instead of the entire
video as illustrated in Figure 638.
EDIUS — User Reference Guide 547