@Jean-Marc_Digne
I have the impression that there is a kind of pinkish cast on the white fur of the dog .
Examining the image, as it is downsized and converted in jpg, I cannot decide if the strong artifacts come from the downsize/conversion or from denoising.
Downsizing permits also to average the noise.
I think as for @Jean-Marc_Digne, your denoising is too strong. The background is denoised but to the detriment of the black fur , mainly around the right eye, giving a plastic aspect.
Also just above the nose where the aspect of small bristle can be confused with noise.
I wouldn’t expect wonders with that amount of noise. It is always a compromise between denoising and loosing details.
For the color fringing in nose and fur I used the defringe module with lowest threshold
I don’t deal with noise in my minimalist processing because I don’t know how to do it properly. Low frequency noise is especially challenging. Observe the colour noise of the nose below (exaggerated for the web).
Wow, some great examples, I’ve got a lot to learn.
I know it’s not open source, but here’s what Topaz Denoise did with this picture. Similar to the first picture I developed the raw in Darktable 3.0 but with only chroma noise reduction, no sharpening, no luma reduction. Then in Topaz with only noise reduction, no sharpening, no ‘enhance detail’ whatever that does.
@clennep Thanks for your kind words. Perhaps my obsession with b&w shows my age. Most of the family pictures in our photo album when I was a child were taken by my Dad with a Polaroid that folded up and had a timer to let you know when photo was ready to peel open. I try to find a way to mimic the way those old photos rendered, but am not always successful. Thanks again!
@sls141 I appreciate your contributions as well. Been saving on bandwidth, so I didn’t look at your B&W closely until now. I like it more than the colour version. It has a nice balance of tones.