Belden Grass Valley GV Korona, Руководство пользователя

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Video Mix/Effects
Chroma Key
• Preset Pattern
• Chroma Key (option)
The GV Switcher system also supports self keys and split keys.
Chroma Key
The GV Switcher system features the chroma keyers option with powerful controls. These
controls offer subtle adjustments to allow successful keying of difficult subject matter (fine
hair, smoke, translucent objects, etc.), and to overcome some problems resulting from
imperfect chroma key set coloring or lighting. The GV Switcher chroma key also has an Auto
Setup feature that can create an excellent chroma key under most circumstances without
the need for manual adjustment.
The following information provides more detailed instructions on how to set up a chroma
key using the Auto Setup feature and use the manual controls in the Keyer menu.
Chroma Key Auto Setup
The first step of setting up most chroma keys is to use Auto Setup. Auto Setup automates
the first steps to achieving a chroma key. Auto Setup performs the following:
• Calculates primary suppression Hue and Luminance.
• Sets primary suppression Selectivity and Chroma to defaults.
• Calculates Clip Low, and sets Clip Hi to default.
• Sets all the secondary suppression values to duplicate the primary suppression values,
but turns secondary suppression off.
• Changes Opacity temporarily to 100% to permit an accurate backing color sample, and
then returns it to its original setting.
• Sets Key Position and Size values to default (0).
Two different Auto Setup algorithms are available, one for well designed and lighted sets
(
Reshape off ), and the other for more challenging sets ( Reshape on). Depending on
individual circumstances, additional manual adjustments may be required after you use
Auto Setup.
After an Auto Setup has been initiated, you can cancel it by pressing the Auto Setup button
again, but the chroma key will retain the default settings imposed.
Manual Chroma Key Adjustments
If the Auto Setup of the hue fails to provide a suitable chroma key, additional controls are
available in the Keyer, Mode menu for fine tuning the key. Chroma key manual set up
consists of choosing the best set of compromises to provide adequate detail and color
fidelity to meet your needs. While using this menu you need to view the chroma key scene
on a monitor. A vectorscope and waveform monitor can also be very useful when setting
up a chroma key. During set up you need to focus your attention on particular areas of the
foreground, background, and/or composite. The areas you look at will change depending
on the individual controls being used. The
FG Only and BG Only menu buttons can be used
to remove extraneous picture information, allowing you to view only those areas of the
composite.