Apple Shake 4 - Manual (Page 713)

Chapter 24 Keying 713
operator
Each button that appears in the group of controls labelled “operator” allows you to
modify the key created by Primatte, using a color you select with the Color control. The
effect of all the operators you click is cumulative, and each operation you perform is
saved in a history of operations that’s accessible via the currentOp slider.
Every time you click an operator, an additional operation is added to the history of
operations represented by the currentOp slider. To modify the currently selected
operation, instead of adding a new one, select an operation using the currentOp slider,
click the color control bearing that operation’s name, then scrub the image to select a
new color range.
The eight operator buttons include the following:
• background: Assigns pixels to the background. Areas of the foreground that you
select with the background operator become100-percent transparent, with no spill
suppression.
• restore detail: Removes transparency on background material. It is useful for
restoring lost details such as hair. It is the equivalent of detailTrans in the “fine
tuning” subtree, but with no slider.
• fine tuning: When the fine tuning mode is clicked, three additional parameters
appear at the bottom of the Parameters tab.
• spillSponge: When this mode is selected, the pointer motion in the Decolor slider
performs a color adjustment of the sampled color against the background. After
sampling a color region from the image, the more to the right the pointer moves,
the less of the background color component (or spill) is included in that color
region. The more to the left the pointer moves, the closer the color component of
the selected region is to the spill suppress color.
• fgTrans: Adjusts the transparency of the matte against the sampled color. After
sampling a color region from the image, the more to the right the pointer moves,
the more transparent the matte becomes in that color region. This is equivalent to
the “make fg trans” button, but offers more control.
• detailTrans: Determines the transparency of the sampled color when it is close to the
background color. The slider in this mode is useful for restoring the color of pixels
that are faded due to similarity to the background color. If you slide to the left,
picked areas are more opaque. This is equivalent to the “restore detail” button, but
offers more control.
• foreground: When this mode is selected, the sampled pixels within the image
window become 100 percent foreground. The color of the sampled pixels is the same
color as in the original foreground image. The matte is completely white.
• make fg trans: Allows you to select regions within foreground elements in order to
make them more transparent. This operation is used to adjust elements like clouds or
smoke. It is the equivalent of the fgTrans conrol in fine tuning mode, except that it
features no slider control.