User Manual

of the image at a given Motion Threshold setting. A Large setting assumes fast motion
with blur occupying a larger area of the image, which excludes more of the image from
Temporal NR at the same Motion Threshold setting. Choose the setting that gives you
the best compromise between a reduction in noise and the introduction of motion
artifacts when adjusting the Motion Threshold parameter.
 Luma Threshold: Lets you determine how much or how little Temporal NR to apply
to the luma component of the image. The range is 0–100, where 0 applies no noise
reduction at all, and 100 is the maximum amount. Too high a setting may eliminate fine
detail from the image.
 Chroma Threshold: Lets you determine how much or how little Temporal NR to apply
to the chroma component of the image. The range is 0–100, where 0 applies no noise
reduction at all, and 100 is the maximum amount. Too high a setting may eliminate fine
color detail from the image, although you may find you can raise the Chroma Threshold
higher than the Luma Threshold with less noticeable artifacting.
 Luma/Chroma Threshold ganging: Ordinarily, the Luma and Chroma Threshold
parameters are ganged together so that adjusting one adjusts both. However, you can
ungang these parameters in order to adjust different amounts of noise reduction to
each component of the image, depending on where the noise happens to be worst.
 Motion Threshold: Defines the threshold separating which moving pixels are in motion
(above this threshold) versus which moving pixels are static (below this threshold).
Using Motion Estimation, Temporal Noise Reduction is not applied to regions of the
image that fall above this threshold, in order to prevent motion artifacts by not applying
frame-averaging to parts of the image that are in motion. Lower values omit more of the
image from Temporal NR by considering more subtle movements. Higher values apply
Temporal NR to more of the image by requiring faster motion for exclusion. You can
choose between 0 and 100, where 0 applies Temporal NR to no pixels, and 100 applies
Temporal NR to all pixels. The default value is 50, which is a suitable compromise for
many clips. Be aware that if you set too high a Motion Threshold, you may see artifacts
in moving parts of the image.
 NR Blend: Lets you dissolve between the image as it’s being affected by the
Temporal NR parameters (at 0.0) and the image with no noise reduction at all (100.0).
This parameter lets you easily split the difference when using aggressive temporal
noise reduction.
Spatial NR Controls
The Spatial NR controls let you smooth out regions of high-frequency noise throughout the
image, while attempting to avoid softening by preserving detail. It’s effective for reducing noise
that Temporal NR can’t.
 Mode: The Mode drop-down lets you switch Spatial NR between three different
algorithms. All three modes of operation use exactly the same controls, so you can
switch between modes using the same settings to compare your results.
–
Faster: Uses a computationally lightweight method of noise reduction that’s good at
lower settings, but may produce artifacts when applied at higher values.
–
Better: Switches the Spatial NR controls to use a higher quality algorithm that
produces greatly superior results to Faster, at the expense of being more processor
intensive to render, as well as not allowing you to decouple the Luma and Chroma
Threshold sliders for individual adjustments to each color component.
–
Enhanced: Does a significantly better job of preserving image sharpness and detail
when raising the Spatial Threshold sliders to eliminate noise. This improvement is
particularly apparent when the Spatial Threshold sliders are raised to high values
Chapter – 134 The Motion Effects and Blur Palettes 2993