Blackmagicdesign cintel, Installation And Operation Manual

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Setting ‘radius’ to be progressively larger results in higher quality within areas of
greater visual detail at high luma and chroma threshold values, at the expense of slower
performance. An NR radius of ‘medium’ should provide suitable quality for most images
when using medium NR threshold settings. As with many operations, there’s an
adjustable tradeoff between quality and speed.
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Luma Threshold: Lets you determine how much or how little noise reduction 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.
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Chroma Threshold: Lets you determine how much or how little noise reduction to
apply to the chroma component of the image by smoothing out regions of high-
frequency noise while attempting to preserve the sharpness of significant edge details.
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.
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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. For example, if an image softens too much at a certain
level of noise reduction, but you find there’s more color speckling than there is luma
noise, you can lower the luma threshold to preserve detail while raising the chroma
threshold to eliminate color noise.
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NR Blend: Lets you dissolve between the image as it’s being affected by the spatial 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 spatial noise reduction.
Suggested workflow
We recommend the following steps for reducing noise in your scans without losing too much
detail. Of course, over time you will develop your own workflow, but this is a good start.
Applying noise reduction to an image:
1 Enable temporal NR by choosing 1 to 5 frames from the ‘number of frames’ pop-up
menu. Keep in mind that more frames dramatically increase the render time of this
effect, while it may or may not significantly improve the result, depending on your
material.
2 Choose options from the ‘motion est. type’ and ‘motion range’ pop-up menus
corresponding to how much motion is in the image. If there’s a lot of motion, you may
need to choose ‘better’ and ‘large’. If there’s not very much motion, lesser settings
may suffice.
3 With luma and chroma threshold linked, slowly raise either parameter until you just
start to see a reduction in noise within the non-moving areas of the image, then make
smaller adjustments to determine the maximum amount of temporal NR you can add
without creating motion artifacts, or overly softening image detail you want to preserve.
4 If there’s obviously more chroma than luma noise in the image, you can disable luma/
chroma linking at a satisfactory level of luma noise reduction, and then raise the
chroma threshold to apply more aggressive temporal NR to address color speckling in
the picture.
84 Working with Clips in DaVinci Resolve