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This topic contains 3 replies, has 3 voices, and was last updated by  sam4 1 year, 11 months ago.

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  • #18504

    Steve Cook
    Participant

    Hey…

    Asking the collective what techniques do you use for noise reduction within Mistika?

    Do you use multiple instances of noise reduction or just one node?

    Or external software (i.e. NeatVideo/Resolve)

    thanks in advance

    Steve

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  • #18506

    sam4
    Participant

    Neat Video is Gold Steve. That’s always my ideal solution.

    If you’re using Mistika’s Denoise then I do following (this is my ideal workflow): I usually dedicate 1 of the 4 additional inputs to ColourGrade as ‘Beauty Pass’. By this I mean an extremely clean version of the images that you’re working with on Input #1. The reason that I do this is because you can get artifacts from the Denoise effect (with Temporal) but I get around that by using the result as an Input that I recover. I call this: ‘Leaving the artefacts behind‘.

    Here’s my logic:

    Most of the time you only want to denoise the blacks, as that’s where the noise is. Using a Vector to key the blacks and then Recover Input #2 (the denoised image) though will denoise the blacks cleanly – as most artefacts will be at the brighter end of the spectrum. I’ve also built several ‘Atifact Protection’ effects for myself that I store in FXPresets. This is the result of the Edge Detect that I built: http://imgur.com/a/vykIy

    I usually ‘store’ the EdgeDetect in the KeySource Channel. It’s extremely useful for all kinds of things.

    Also – don’t get stuck on the name alone – just because it doesn’t say ‘Denoise’ doesn’t mean that it can’t be used for that. I often combine the BLUR:MEDIUM effect with an inverse EdgeDetect. That will blur the bits that you want and leave the edges (detail) sharp. Medium Blurs are expensive so I usually render a Denoise/Blur track which is my Input #2. So as well as doing things like keying the blacks, I will also key fleash tones and Recover the Denoise/Blur layer through for beauty work.

    One other quick trick – artifacts are mostly in Luma. So before I denoise I usually BlurChroma using the Mistika blur effect. Again – the trick is to use Medium Blur. Gaussian Blur for Promist Filters, Circle Blur for Defocus.

    Hopefully you know how to use the artifact filter key within the Denoise effect. If you don’t know what I mean then set VIEW to ALPHA while on the Denoise effect and you’ll see what I mean.

    Helpful?

    #18507

    Anonymous

    Yeah, I use NeatVideo as well. It’s pretty awesome.

    #18508

    sam4
    Participant

    I don’t know the details but I do know that a lot of SGO development time went into integrating Neat Video with Mistika as much as possible, including in improving the render time when using Neat Video in Mistika.

    I used to work for Park Road Post Production in New Zealand and I know that at least 99% of the final Hobbit film went through Neat Video in the grading phase of the work. In terms of quality it’s the best I’ve come across for anything short of £10, 000. And it’s only £300 for the full thing.

    Like I said though – if you have the space I would render a ‘Clean’ version of your source material and use the ‘Clean’ version as a 2nd Input to a ColourGrade effect. That way there’s no slowing down the grade while Neat Video renders for real-time playback, and you can always delete the extra track later and still be able to render the Deliverables without it. Or you could use Mistika’s Cache tools. It’s personal opinion but I found that I got a lot more control in a grade when I re-rendered those effects that can be expensive in terms of processing. Denoise, Medium Blurs and anything Optical Flow require the system to calculate a transform for every pixel in every frame; so you can understand why that might slow things down when working with RED RAW .r3d files for a 4K project using a 4K display.

    If Neat Video isn’t available then you can use techniques like I wrote above to get the best out of Mistika’s Denoise without having to worry about artifacts – and once you’ve saved a preset for it then using it in the future becomes no big deal.

    But SGO did put a lot of work into Neat Video support, and it costs less than a day’s catering costs for most facilities 😀

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