About The Luma Key; Multiply Key And Screen Key - Adobe PREMIERE PRO 2 Manual

The following Non Red Key settings are adjusted in the Effect Controls panel:
Sets the levels of blue or green that determine transparent areas in the clip. Dragging the Threshold slider
Threshold
to the left increases the amount of transparency. Use the Mask Only option to view the black (transparent) areas as
you move the Threshold slider.
Sets the opacity of nontransparent areas specified by the Threshold slider. Higher values increase trans-
Cutoff
parency. Drag to the right until the opaque area reaches a satisfactory level.
Removes residual green or blue screen color from the edges of the opaque areas of a clip. Choose None
Defringing
to disable defringing. Choose Green or Blue to remove a residual edge from green-screen or blue-screen footage,
respectively.
Specifies the amount of anti-aliasing (softening) that Adobe Premiere Pro applies to the boundary
Smoothing
between transparent and opaque regions. Choose None to produce sharp edges, with no anti-aliasing. This option is
useful when you want to preserve sharp lines, such as those in titles. Choose Low or High to produce different
amounts of smoothing.
Displays only the clip's alpha channel. Black represents transparent areas, white represents opaque areas,
Mask Only
and gray represents partially transparent areas.
See also
"About keying" on page 355

About the Luma Key

The Luma Key creates transparency for darker values in the image, leaving brighter colors opaque. Use the Luma Key
to create a subtle superimposition or to key out dark areas.
Adjust the following settings as necessary:
Specifies the range of darker values that are transparent. Higher values increase the range of transparency.
Threshold
Sets the opacity of nontransparent areas specified by the Threshold slider. Higher values increase trans-
Cutoff
parency.
You can also use the Luma Key to key out light areas by setting Threshold to a low value and Cutoff to a high value.
See also
"About keying" on page 355

Multiply Key and Screen Key

The Multiply Key creates transparency in the bright areas of the clip. Conversely, the Screen Key creates transparency
in the dark areas of the clip. Like the Luma Key, the Multiply and Screen Keys are most effective when the image that
you are keying contains highly contrasting dark and light areas.
The following Multiply Key and Screen Key settings are adjusted in the Effect Controls panel:
Reduces the opacity of the clip being keyed. Drag the control to the left to reduce the clip's opacity.
Opacity
Determines the luminance level required for an area to be transparent. Drag the control to the left to decrease
Cutoff
the required luminance level.
ADOBE PREMIERE PRO 2.0 363
User Guide