DT Noise reduction poor results – Advice requested

If you really want to compare the two programs, please make sure that exposure and white balance are as similar as possible between the two images: in this case, the DT version is clearly warmer and has a higher exposure (==more amplification of noise).

Also, it’s hard to suggest where you can improve the DT treatment, as you don’t give any details. A screenshot of the settings you use in the denoise module (and perhaps the history stack) would be very useful.
Alternatively, you could post the raw + the xmp file from dt (with a proper license statement, see the “playraw” section here), so others here can have a go.

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Please share a this raw file so we can help you better.
We can’t do much without a raw file.
I promise you, DT has better noise reduction than LT. You just have to know how to achieve the desired result.


Thank for these comments. Yes, the LR result is not perfect; far from it. It was just a quick attempt (about 2 minutes of work) to see what I could achieve quickly on this old image - a sort of basis for comparison.

I would be most grateful if community member could work on the original, so I will try to understand what ‘PlayRaw’ means, as it’s a term that is currently unknown to me. Thank you for the pointer to other videos.

There is a subsection of this forum, Processing > PlayRaw. Make a new post, upload your raw files, assign a license to the raw files, and write a bit about what you want to achieve, then people will edit that file and provide you the sidecar, which you can download and load into your editor to inspect what they’ve done.

You are quite right: I haven’t given enough detail - mainly because, without asking first, I really did not understand what detail would be helpful/necessary for better informed community members to make a meaningful comment. Now I’ve learned a little and will post some screen shots. Yes, I’m going to try to post the raw xmp files (the DT one, not the LR one) to the community once I have understood how to do this.

See also PlayRaw stuff to keep in mind

Yes, having seen what Bruce Williams was able to achieve, I am sure DT can do a better job than LR - right now I’m not sure I can ‘ask’ DT, in the right way, to do it! I’ll be posting a raw file just as soon as I’m confident of being able to do it.

I have taken 2 screen shots, the earlier one showing the contents of the history stack (plus the image) and the later one showing the settings I applied in Denoise (Profiled). I have failed to understand how to license these images so I cannot use PlayRaw yet. In the meantime, I would say there are two major objectives for the post processing of this mage that I would like to achieve: 1). Reduce the luminance and chrominance noise; 2). Recover the blown out detail in the windows - these have intricate metal tracery in them which I was able to reveal very quickly with one single adjustment to the highlights in LR.

In your play raw post say “images licensed under <license name, preferably some CC license>” and that is it.

@LateJunction, you probably haven’t reached to that episode yet, but earlier this year Bruce Williams revisited the “denoise (profiled)” module with dt 3.0:

Some of the advice from version 2.6 has changed since that time.

Just a quick advice from what I find in your screenshot of the history.

you are still using old modules like basecurve and sharpen, which are part of display-referred workflow in Lab space. with dt 3.2.1 you probably should/want switch to the new scene-referred workflow (Exposure + Filmic) using a linear RGB pipeline. That will improve a lot of your possibilities to recover highlights (2nd objective).

For denoise (profiled) I prefer nonlocalmeans mode and a single instance. a good starting point is the auto preset. set autoadjustment slider to same value as your exposure compensation for this picture (compensate visually for middle grey in combination with Filmic). Many times this may be sufficient. if not: switch to manual mode and tweak the result.

you should watch the explanation vids from the devs


denoise (profiled) in non local means mode (or non local means auto) with setting central pixel weight (details) to 1.0 might be an option to suppress the chroma noise


In this screenshot:

  • you should keep the U0V0 curve normal or increase it as it affects chrominance noise reduction
  • you can lower the Y0 curve if you want to preverve luminance noise
  • no need to use a color blending mode. The Y0U0V0 mode already allows to reduce separately chrominance noise from luminance noise
  • you can increase strength (even values higher than 4 are possible using right-click with a keyboard entry)

Thanks, I’ll try that shortly.

I think I was deterred from trying to use scene-referred workflow when I found that “exposure plus filmic” produced a result on another test image (portrait shot of two young friends) which was so extremely ‘plastic’ looking, where as a quick adjustment in LR produced a result which was very satisfying indeed. But I hear what you say and will go back to have another attempt at this, reflecting the other advice I have received. All of it most helpful.

Many thanks for this - you are right, I had not reached that episode yet but now I’ll look at it and try again.

OK, I botched together a new post in the ‘Processing>Play Raw’ category, copying somebody else’s license statement and included links to the raw file and the (DT) xmp. But, embarrassingly, I was unable to figure out how to include a view of the image in the post. :confused:

Just drag-and-drop the exported jpeg into the post.

Ah, that totally explains my difficulty - failure to retain the jpeg !.

Usually with a PlayRAW the poster makes their own attempt at processing with their tool of choice and posts their exported JPEG, though it’s not mandatory.

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