5.5

1059Motion User Guide
Important: After you switch to Manual mode, it’s inadvisable to switch back to Scrub
Boxes mode. For best results, begin keying an image using the Sample Color and Edges
tools in Scrub Boxes mode. Switch to Manual mode afterwards if you feel it’s necessary
to refine your matte using the Chroma and Luma controls. However, after you switch to
Manual mode, do not switch back to Scrub Boxes mode. If you do, you may experience
unexpected combinations of additionally sampled and keyframed values that are
difficult to control.
• Chroma: Two graphic controls in the color wheel control to adjust the isolated range of
hue and saturation that help define the keyed matte. The selected Graph mode governs
which graphs in the color wheel are adjustable. The outer graph controls the softness
(edge transparency) of the matte you’re creating, and can be adjusted in either Scrub
Boxes or Manual mode. The inner graph controls tolerance (core transparency), and is
only adjustable when in Manual mode.
Drag any side of either graphic control to expand or contract the graph’s border, adding
to or subtracting from the range of hue and saturation contributing to the key. In
manual mode, you can also drag inside the tolerance graphic control to adjust its overall
position in the color wheel.
To the left of the color wheel, a small graph displays the slope of chroma rolloff, the
relative softness of matte edges in regions most affected by the Chroma control.
Dragging the Chroma Rolloff slider (described below) modifies the shape of this slope.
It’s possible to zoom into and pan around the Chroma control to more precisely adjust
the graphs:
• To zoom incrementally into the Chroma control, press and hold the Z key and click
the color wheel. To zoom out, press and hold the Option and Z keys and click the
color wheel. To smoothly zoom out, press and hold the Z key and drag left in the
color wheel. To smoothly zoom in, press and hold the Z key and drag right in the
color wheel. You can also press and hold the Space bar and Command key (in that
order) and drag left in the color wheel to zoom out or drag right to zoom in.
• To pan in the Chroma control, press and hold the H key and drag in the color wheel.
You can also press and hold the Space bar and drag in the color wheel in the
direction you want to move it.
• To reset the zoom and recenter the Chroma control, move the pointer over the
Chroma control and press Shift-Z.
• Luma: A grayscale gradient control with adjustable handles to modify the isolated
range of the luma channel (the range of lightness and darkness) that also helps define
the keyed matte. The upper handles (which only appear in Manual mode) adjust the
tolerance (core transparency) of the luma channel’s contribution to the key. The lower
handles adjust the softness (edge transparency) of the luma channel’s contribution to
the key.
The Graph mode governs which handles are adjustable. In Scrub Boxes mode, you can
adjust only the lower softness handles. In addition to using the handles, you can drag
the slope in the graph to adjust the softness.
In Manual mode, you can also adjust the upper tolerance handles, which modify core
transparency within the luma channel of the matte. Dragging the slope in the graph
adjusts the lower handles (the softness). To adjust all handles simultaneously, drag
inside the curve in the gradient control.