User guide

104
Chapter 6, Setting Up Realtime Effects with Adobe Premiere
$ Hue Use this to rotate the color selector around the perimeter of the color
spectrum so that you can select different hues (colors) on which to key.
$ Saturation Use this to select colors that have a particular saturation
value. Pale colors have a low saturation value and are located at or near the
center of the spectrum. Vivid colors have a high saturation value and are
located at or near the perimeter of the spectrum. Because pale colors have
low saturation, you’ll find them more difficult to key on than the vivid
colors.
$ Luminance Use this to select the colors that have a particular luminance
value. A luminance selector in the
Luma Plot (Plot view) or Luma Map
(Map view) indicates the particular luminance value you’ve selected.
$ Aperture Use this to widen or narrow the aperture of the color selector
to increase or decrease the range of colors on which you want to key.
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Fine-tune Keyer Controls Use the following controls to fine-tune your
chroma key effect:
$ Softness Use this to soften the edges of your key by blending parts of
your foreground image with your underlying image. This makes certain
areas of your foreground image partially transparent instead of completely
transparent or opaque.
$ Spill Removal Use this to remove the contamination (spill) that your key
color may leave on or around the edges of your foreground image. Spill is
usually caused by light reflecting from your solid color backdrop (key
color) onto your foreground image.
Spill Removal replaces your key color
from the “spill areas” with the opposite color in the spectrum, which returns
a more natural look to these areas.
For example, after applying a chroma key effect to a foreground image of
a newscaster against a blue backdrop, you may find that there’s a blue
reflection in the newscaster’s skin and hair. Increasing the
Spill Removal
level removes the blue pixels by adding yellow to these areas.
$ Saturation Threshold Use this to proportionally increase or decrease
the region outside of your saturation range. This controls how closely the
Saturation value specified under Keyer Controls must match the key
color before a region becomes transparent.
For example, after applying a chroma key effect to a foreground image that
includes dark areas or shadows that you want to preserve in your effect, you
may find that these areas have become semi-transparent. By adjusting the
Saturation Threshold, you can eliminate the key color from these dark
areas, so that they’ll become completely opaque.
$ Shadow Suppression Use this to make shadows in your clip less
apparent. A higher value indicates less shadow.