The problem is to figure out what are fine details and what is noise. 
If one can filter out just the fine details, one could create a diff with the original source and thus create a mask that could be used with the denoised to re-add these details.
Hybrid does not have a mask for fine detail/grain since I don't know of a way to generically identify it.
Alternatively, you can add new grain after the filtering.
Can you share a sample of the scene where you want to keep the details?
Cu Selur
Ps.: https://silentaperture.gitlab.io/mdbook-...sking.html might be interessting for understanding masking.
PPs.: You might want to try whether using an inverted 'EdgeMask (Prewitt)' shrunk by -1 or -2 might work.
If one can filter out just the fine details, one could create a diff with the original source and thus create a mask that could be used with the denoised to re-add these details.
Hybrid does not have a mask for fine detail/grain since I don't know of a way to generically identify it.
Alternatively, you can add new grain after the filtering.
Can you share a sample of the scene where you want to keep the details?
Cu Selur
Ps.: https://silentaperture.gitlab.io/mdbook-...sking.html might be interessting for understanding masking.
PPs.: You might want to try whether using an inverted 'EdgeMask (Prewitt)' shrunk by -1 or -2 might work.
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Dev versions are in the 'experimental'-folder of my GoogleDrive, which is linked on the download page.
Dev versions are in the 'experimental'-folder of my GoogleDrive, which is linked on the download page.