GRASS VALLEY EDIUS VERSION 5.1 User Reference Manual page 552

Section 6 — Effects and Titles
552
Figure 644. Luminancekey Configuration Dialog
4. Configure the effect settings per the explanations below and click the
button to close the dialog.
Luminance Range Selection
To specify the range over which luminance key settings apply, move the
slope, minimum and maximum sliders or enter the desired numeric values
directly into the corresponding entry fields.
Figure 645. Luminance Key Range Selection
Luminance settings are applied to the selected area of the video as follows:
Gradual Increase
The range between the first Slope slider and the Minimum slider is
range over which luminance effects will be gradually increased from 0
to 100%.
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