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Kayenne/Karrera/GV Korona
User Manual
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individual scene. You may need to go back to earlier steps and readjust previous settings to
optimize the key. Understanding what the chroma key controls do will help you decide
what adjustments are required for your individual situation.
Primary Suppression
Primary suppression is the most critical chroma key parameter, and the easiest to set. Auto
Setup should take care of this, but manual adjustments in the Keyer, Mode menu can be
made if desired. If primary suppression is set wrong, however, it will be impossible to
achieve a good chroma key with the other controls.
Six Keyer System Example
Primary Suppression should be set while looking at the foreground. Ideally the backing
color will appear as a small dot on the vector scope and a perfectly flat line on the
waveform display, but this never occurs due to set lighting variations, shadows, etc. This
means you will need to pick the best suppression for the overall look of the key.
You can select the stage 1
Pri Suppress data pad, if necessary, to activate these controls and
adjust Hue, Selectivity, Chroma, and Luma primary suppression to eliminate the backing
color.
• Hue can be set accurately with Auto Setup. Hue should center on the primary color of
the backing area of the foreground scene. Depending on where Luma and Chroma
primary suppression are set, adjusting Hue may not make any noticeable change on
the scene. Chroma suppression should be preset to 100% and Luma set to 0%. Hue can
then be tuned to remove the backing color.
• Selectivity may need to be increased if there are colors in the foreground image that
are being suppressed. Selectivity should be set as low as possible without including
colors that should not be suppressed. For example, when keying on green, a greenish
yellow shirt might be affected by the suppression. If so, adjust the selectivity high
enough to reject that color. Too high a selectivity is one of the classic causes of a noisy
key. If the foreground subject is stationary, consider using a force mask instead of
increasing selectivity.
•
Chroma
suppression can be set accurately with Auto Setup. To adjust, increase Chroma
suppression and observe the backing color dot on the vector scope move toward the
center. You want to center it exactly, so no chroma exists in the backing area. 100%