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Description of all Commotion Clip FX
Matte Feather
Matte Feather creates a gradual change (feathering) from opaque to transparent at the edge of a layer’s
alpha channel. You can use it to correct dirty or ragged layer edges where the keyer wasn’t precise
enough. It can also soften a hard edge on a computer-generated object to help make the object fit into an
organic scene.
Approximately 70% of all layers can be fixed using just Feather Width, Edge Threshold, and Edge Post
Blur. If Edge Post Blur is not subtle or precise enough, set it to 0% and follow your Matte Feather effect
with an Edge Blur effect. Very high Feather Width settings can create edge-density effects that make
clouds or glass objects appear more real.
Matte Feather may appear to have the same effect as such effects as Edge Blur, but feathering and blurring
are two different things. Edge blurring can produce a feathered edge, but an edge feather modifies only
the alpha channel and doesn’t directly affect the RGB channels. This makes it the better choice for feath-
ering rough or jagged matte edges.
Matte Feather gives you a great amount of control over where and how the matte feather is applied. This
feature is very useful when you are compositing problematic layers.
 Edge Pre-Blur-
blurs the edge of the alpha channel before the feathering effect is applied, helping to eliminate jag-
gies. We recommend that you use low settings, because this control changes the shape of the edge
and may cut into the layer in ways you don’t want if it is set too high.
 Edge Smoothing -
smooths the edge of the alpha channel into a rounder shape. This control is good for making the
overall edge profile softer. We recommend you use low settings.
 Edge Threshold -
determines where the edge begins to become transparent relative to the absolute edge of the alpha
channel. Higher numbers move the edge threshold inward. A setting of 0 places the feather edge
right at the actual edge of the alpha channel.
 Feather Width -
controls the width of the area affected by the feathering.
 Feather Slope -
specifies the abruptness of the transition from opaque to transparent. Lower numbers make the
transition more gradual.
 Edge Post Blur -
adds a blur effect to the edges using the Super Blur algorithm, removing any remaining edge
hardness.