Apple Color 1.0 User Manual
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Chapter 11
Color FX
 Green Gamma: Adjusts the green channel only, enabling color correction based on a
gamma adjustment for that channel.
 Blue Gamma: Adjusts the blue channel only, enabling color correction based on a
gamma adjustment for that channel.
Grain Reduction
Reduces grain and noise in an image by averaging adjacent pixels in that frame
according to the values specified in the Master, Red, Green, and Blue Scale parameters.
Edge detection can be used to preserve sharpness in areas of high-contrast detail via
the Edge Retention parameter, and a sharpening operation can be applied after grain
reduction to boost overall detail. Because some shots have noise that’s more apparent
in specific color channels, you can make independent adjustments to each channel.
This node has six parameters:
 Master Scale: Averages the adjacent pixels of every color channel in the image to
reduce grain and noise, at the expense of a certain amount of image softness.
 Red Scale: Selectively averages pixels in the red channel.
 Green Scale: Selectively averages pixels in the green channel.
 Blue Scale: Selectively averages pixels in the blue channel.
 Edge Retention: Uses edge detection to isolate areas of high-contrast detail in the
image (such as hair, eyes, and lips in an actor’s close-up), and excludes those areas of
the image from the grain reduction operation to preserve the most valuable image
detail from softening. Higher values preserve more of the original image in these
areas.
 Post Sharpening: Applies a sharpening convolution filter after the grain reduction
operation to try and restore some lost detail once the grain has been softened. Use
this parameter sparingly–if you set this too high, you’ll end up reintroducing the
grain you’re trying to reduce.
Hue
Rotates the hue of every pixel in the entire image. This node has one parameter:
 Shift: The amount by which you want to shift the hue. This is not done in degrees, as
is represented in the Vectorscope. Instead, you use a value from –1 to 1, where –1, 0,
and 1 place the hue at the original values.
Invert
Inverts the image. Useful for creating “positives” from image negative. Also useful for
reversing a grayscale image that you’re using as a matte with the Alpha Blend node, to
reverse the portions of the matte will be solid and transparent.