Good Noise remover for Linux - does it exist?

As a professional photographer that grew business using LR and PS, I’ve had a bit of ups and downs to ‘translate’ it to Linux and its programs, most notably RAW converters. It’s been a fun journey with lots of stuff to learn and re-learn, but sometimes I tend to miss certain features.

My preferred choice is RawTherapee. I cannot use Darktable at all, that’s totally out of question.

Now, I’m having a hard time with luminance noise removing in Raw Therapee in high iso (+6400) images. Compared to LR’s dealing with noise, it sucks. Big time. Or maybe I didn’t find the sweet spot yet?

But what I currently have is either:

a) Images with 0% lumi noise removed, all the detail is there, but grain is as large as the roughest sand paper, even when downscaled to monitor resolution.

b) Slightly removed noise, but artifacts kicking in. Nothing to be happy about, detail is compromised, noise is still prominent. So I tend to stick with a).

c) Aggressive noise removal, noise is removed but so is the detail with severe artifacts showing wherever there’s the detail.

What can I do? Is there a good 3rd party plugin for Gimp or stand alone program for Linux? Or maybe I’m missing something in RT?

Thanks!

Hi,
I suggest that you share examples, preferably raw. Otherwise it’s hard to understand what you mean.

That said, there is at least one commercial noise removal tool available for linux (I don’t remember the name, but probably google can find it). Whether it’s good or not, though, depends a lot on taste…

found it, it’s called “neat image”

1 Like

Hi @maboleth,

Two swift questions:
What camera are you using?
Why can’t you use darktable at all?

Have fun!
Claes in Lund, Sweden

Thanks so much, Neat was great when I used it in the past, didn’t know it was available in Linux too!

I just downloaded the demo and will try it.
As for RAW examples, if I get something ready I’ll show.

@Claes, hi there! I’m using Canon 5dmkiv. I cannot use darktable due to the user interface that I dislike and no 2nd monitor support.

The 2nd monitor support should be in DT 3 iirc.

1 Like

Nice. However, speaking of DT, its noise removal was the worst I tried or required lots of tweaking to get it right. For example, the chroma noise. In RT it’s mostly flawless and automatic, it just works, while in DT it was very bad and I had to use many sliders to try to remove it. Not sure if they made something better in recent editions though.

Anyway, I find RT perfect for my needs, if only I could tweak the noise the way I like it. BUT @agriggio helped me with Neat image suggestion, so there’s no need to try it anymore. It works great in Linux and gets the job done fast, even demo edition is totally useful. I’m happy. :slight_smile:

Thanks guys! This was some super fast help.

Hello @maboleth

With G’MIC 2.9 (installed as plugin on Gimp 2.10.18) you get plenty of Noise reduction filters.

For instance:

Never tried them in depth, though.
Luckilly, I can always take my pictures at 200 ISO, tops…

As suggested, if you provide a RAW sample we can test it ourselves.
Better yet, you could provide it on the “Play RAW” section of this forum so that everyone can have some fun with it.
Since most of us are confined in our homes (due to the Corona virus scourge) we have plenty of time… :slight_smile:

1 Like

It seems that you have your solution already. Congrats!

But I can’t help myself and I have to tell there another option within RT: it’s a really really powerful denoising option, though it’s not a single slider, nor semi-automatic. On the other hand, not being a single slider is really its strong point.

I’m talking about the Denoise and Refine module (sub-tool) inside the Wavelet Levels tool: it allows to perform luminance denoising on a per detail size way. You can remove noise and increase local contrast of the remaining details on a per level basis, and it gives way much better results than a simple luminance denoising.

If you’re curious on how to use it, read: http://rawpedia.rawtherapee.com/Wavelets/es using a good translator :smiley:

If you don’t understand it yet, I can write a summary with the most important steps.

5 Likes

Thanks, that’s certainly interesting feature for pin-pointing the grain issue during raw.

I guess it works similarly like Contrast and other Wavelet levels settings, from finest to more coarse, 1-7. I will read rawpedia for more detail. :slight_smile:

1 Like

@maboleth Don’t know if you already tried this but I found I got better results in RT with luminance noise reduction by setting strength to 100 then moving the details slider to a level with an acceptable level of noise and detail. I’m happy with the results, but might not be good enough for you?

2 Likes

You should try then darktable 3, the new profiled denoise is much improved (including auto modes).

1 Like

Yes, I do the same. Generally my goal in removing noise is making it less prominent, but also having it uniform across the whole image.

That means I do not opt for selective noise removal, like 100% noise-free sky then 50% noise building. That looks artificial and overprocessed as hell. Or aggressive noise removal with severe artifacts - that looks like a badly compressed JPG phone image quality.

1 Like

Second that. it was even further improved in 3.0.1 with more control over chroma/luma noise separately.

Relevant video by rawfiner (the developer of the module): https://www.youtube.com/watch?v=7ZhbeXpx2W8&t=2s

Sure, I use NeatImage for Linux - awesome results and really nice upgrade policy too. It is the only non-opensource software I actually use and paid for.

1 Like

OK I did not read the whole thread BUT noise reduction in both RT and dt is far superior to Adobe and many other commercial noise reduction. You need to know how to use them, but it is not so difficult.

2 Likes