the “secret” is the recover details slider in the noise reduction module, and perhaps the gamma slider
I usually sharpen a little bit stronger, then I reduce noise heavily, and then I set recover details to perhaps 90, if there is more noise in dark areas I set gamma to maybe 1,15
It seems also that C1 output has a lot more local contrast.
that too, yes
Thank you very much for the suggestions !
Here is a better attempt at the denoise, quite closer to C1 output.
and also the raw file if you want to play with it :
DSC02852.ARW (23.9 MB)
This file is licensed 
(Creative Commons, By-Attribution, Share-Alike)
OK, thank you.
Please perform this swift test:
In tab 2 (Detail), turn Contrast by Detail Levels ON
(by clicking on the thing to the left of the title Contrast…
Click on Contrast + a few times and see what happens.
This is what I did (with the crop) in darktable. There is always a compromise between detail and noise.
I find that better than the C1.
Can you post the sidecar from this later attempt?
As @gaaned92 said, it has to do with the local contrast. If you look at the original comparison, the shadow behind the sign is darker in the RT version than the C1, and yet the entrance roof tile has lighter greys. This means that contrast is higher globally but lower locally. This makes objects look sharper and more intense.
As for detail, the RT version has more detail and noise, except for the crushed black. This is evident in the wood grain (finer, more continuous) and on the tile surface (looks less like an illustration).
PS Dfine2 looks like a good compromise actually. I would go for something between that and the original RT version.
Here is another variation starting from the bundled High ISO Auto Matched Curve and then using Wavelet Edge Sharpening plus Haze removal and some more tweaking.
DSC02852.jpg.out.pp3 (11.7 KB)
Where do the blue patches all over the metal part come from? I do not see these in my version.
Hermann-Josef
Just for information in real life it’s ceramic tiles, not metal and they do have a blue/gray shine in them.
It’s a small restaurant in the back alleys of Shibuya, Tokyo.
My original intention was a little more run down feeling for this picture, so I feel this version is a little too sharp but technically I bow to the result.
Clearly need to study more the tool !
Pietro
Thanks everybody for the suggestions, I’ll download the pp3 files and have a look in detail.
Here it is my second attempt:
DSC02852.ARW.pp3 (12.0 KB)
@sovereign quoted from RawPedia and @pittendrigh started a new thread on it. I think the language could be misinterpreted. Here is my explanation:
Denoising an image always reduces details, so I denoise only until a point where I start loosing too much details.
For me ISO 8000 is a ‘emergency’ setting when I do need short exposure in bad light conditions.
The picture was taken with an aperture of 7.1 and 1/80 sec. exposure. In my opinion this picture could have been taken with aperture 4-5 and an exposure time maybe at 1/40 or maybe longer dependent on your ability to hold the camera still and the shake reduction capabilities of the camera. In this case the picture could have been taken with a much lower ISO resulting in less noise.
With pictures at such high ISO values I did not find a way to completely get rid of noise and keep all the details that I want. So I only do whats possible without loosing too much details.
In Darktable I was able to get rid of chroma noise, all my attempts to decrease luma noise resulted in loss of detail. Finally I reduced noise using different methods with this result:
According to exif data the widest aperture for this lens/focal length combination is 5.6
I switched cameras recently, my previous one was a M43 Panasonic GF1 so I’m still getting around controlling the depth of field.
I had a 50mm f/1.7 manual Minolta lens in my bag also when shooting but I thought that a larger aperture would make the depth of field too shallow. Already in current image the first and last tiles of the roof are a little soft due to this.
I could have indeed reduced the ISO a little and increased the exposure since it’s not a moving subject but that said, coming from the GF1 where ISO800 was already a complete mess, I’m still amazed of how clean the ISO12500 images come out from the new Sony.
IBIS on this camera has 5.5 stops power, did not try out yet the full extend of what is possible with it.
I found @shreedhar’s settings a very good compromise between noise reduction and detail preservation.
I took those settings, reset any other not related to noise reduction and I’m planning to save these settings as a first denoise step on my workflow.
However, by comparing the before(neutral) and after, I notice that there’s some kind of change in tone. (Not sure if “tone” is the right word here to name the color change I notice).
Just using denoise, plus wavelet denoise and refine, and edge sharpness shoudn’t preserve the same color tonality?
Shreedar’s settings applied to an image I already put in play raw (the AquaRio), after and before:
