We have received some report of Oidn failing to denoise image area with very light shadow. It is like if there is a threshold under which noise is not removed.
This is an example of the problem, the normal rendering:
and the is the Oidn output:
The very end of the monkey shadow is not denoised, there is a quite sharp cutoff.
This is a .zip with the .png/.exr rendering images, albedo and normal AOVs to replicate the problem:
Thanks for reporting this issue! We are currently preparing a new release, which will fix this. This is the produced output with the new version (not final yet):
We have received some report of Oidn failing to denoise image area with very light shadow. It is like if there is a threshold under which noise is not removed.
This is an example of the problem, the normal rendering:
and the is the Oidn output:
The very end of the monkey shadow is not denoised, there is a quite sharp cutoff.
This is a .zip with the .png/.exr rendering images, albedo and normal AOVs to replicate the problem:
img.zip
This is the thread in our forum where the problem is discussed: https://forums.luxcorerender.org/viewtopic.php?f=4&t=1122
From the above forum thread, another example of the problem in a real world scene can be seen here: https://forums.luxcorerender.org/viewtopic.php?f=4&t=1122&start=10#p13302