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8.2.16 Special features
For Chroma Key:
Chroma Keying is used to key from a particular color. It produces a key which is most suitable for moving
images and “weatherman” style applications.
- Color grabber:
Select Chroma Key menu > Select Color grabber menu
Using a crosshair, you can select a particular hue based on what is on screen. Once you have adjusted the
crosshairs to a desired position, press set/enter to capture the color value at that instant. You can then adjust
the other parameters such as Tolerance to further refine your key.
- Manual Setting:
Select Chroma Key menu > Manual Settings menu
•
R,G,B:
these controls allow you to manually select a hue, defined by its Red, Green, and Blue values as you
can find in Windows (Paint software).
•
Tolerance:
the Tolerance parameter allows you to expand your key color selection to include colors which
are similar to the selected value. A tolerance of 1 will select only the desired hue, whereas a tolerance of
255 will select nearly all hues.
•
Black Level:
this option permits adjustment of the luminance levels of the keyed hue. The Black Level is the
luminance lower bound. Colors in the selected hue range with a luminance brighter than the Black Level but
darker than the White Level will be considered part of the key.
•
White Level:
this option permits adjustment of the luminance levels of the keyed hue. The White Level is
the luminance lower bound. Colors in the selected hue range with a luminance brighter than the Black Level
but darker than the White Level will be considered part of the key.
•
Titling alpha:
if you have selected one of the two Titling mode, the titling menu appears. This option places
a transparent black backdrop behind the entire layer to which the key is applied. This effect is useful for
using bright titles on bright backgrounds, such as clouds.
•
Invert keying:
by default, this mode is disabled. When this mode is activated, the key selection will remain
on screen, and all other portions of the image will be keyed away. For example, you would see the green
screen behind the actor, while the actor would be keyed away.
