July 26, 2016 at 12:47AM

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Is anybody else getting grains when LUTs are added in DaVinci Resolve

I've held off asking this question for too long as I was hoping that there are others out there with similar issues with LUTs as me but sadly, (or not so sadly) after a bit of researching, I seem to have no luck. Anyway here's my issue;

I downloaded Implulz and Osiris LUTs and have been using them fairly regularly for a lot of my projects. But, since day one, I've noticed that the moment I apply LUTs, my footage become extremely noisy. I then have to apply neat video to remove the grains. Which I'm not a fan of as it smoothens the skin to some sort of a Barbie doll kind of effect. I'd like to attach a before and after here, but it looks like there isn't a way to attach photos here. Let me know if any of you guys have faced similar issues while working with LUTs in resolve and have found a work-around. Thanks in advance.

6 Comments

Are you working with 8-bit color (which Resolve allows) might be the culprit. I usually run Resolve with at least 10-bit and sometimes 16-bit color (which it also allows, in the Preferences).

July 26, 2016 at 8:19AM, Edited July 26, 8:19AM

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Probably what happens is that the noise which is already there gets more prevalent more due to the LUT making changes in luminance. For instance darker regions tend to be more noisy but they are less visible because they are dark, but when you lighten the darker regions the noise becomes more visible.

It would help if you could show a before and after TIFF file demonstrating the problem.

July 26, 2016 at 2:24PM, Edited July 26, 2:26PM

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Cary Knoop
Member
2421

the noise is in your footage, lut pump up it.
neat video have tons of setup, and is very important to choose where to sample noise, i use from 10 years and also on sd footage, but you can avoid easely the "doll skin effects" (ps i'm agree with you, i hate this result :-P).

July 28, 2016 at 4:33AM

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Carlo Macchiavello
Director
659

After you guys mentioned, I looked at the footage. And lo and behold, you guys were right. There's a ton of grains in the footage. When I add the LUT, it becomes more apparent. You can check out the before and after here.
https://www.dropbox.com/sh/j7aatyor1327yol/AAAip0YqyNSDFMRxTyHaojWea?dl=0

Any suggestions as to what I should change while shooting next? The girl in yellow dress was shot on Red Dragon at 800 ISO and the other was shot on ARRI Amira at 800 ISO.

July 29, 2016 at 11:53AM, Edited July 29, 11:55AM

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Sahit Anand
Director and Co-Founder of DO. Creative Labs
260

Without the log source it is hard to tell if your exposure was right.

I would suspect the yellow dress shot might have been slightly under exposed while the other scene seems to have white balance issues.

Cary Knoop

July 31, 2016 at 9:41PM

With resolve its super important to understand which tools to use for certain circumstances. The LUT may be adding grain, seems to be pushing the image too far especially in the whites.

You may be applying the LUT too early in your node tree, before doing a primary/secondary. You also didn't correct for the highlights after the LUT among other mistakes I see I. The grade.

I doubt he underexposed it that bad when shooting raw, unless it was 3 stops under then he probably knows what he did wrong.

I would suggest watching some Lynda courses on resolve, they will really open up your eyes on how to reduce noise during a grade. Many times using blending modes can help with this, or other tricks resolve has without doing a noise reduction.

August 1, 2016 at 11:47AM

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