openCL render issues: unknown pattern, sporadic white particles with Matte translucent

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FarbigeWelt
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Re: openCL render issues: unknown pattern, sporadic white particles with Matte translucent

Post by FarbigeWelt » Thu Oct 24, 2019 9:16 am

Dade wrote:
Tue Oct 22, 2019 10:04 am
FarbigeWelt wrote:
Fri Oct 18, 2019 10:17 am
I made an animation with my original scene. The pattern is visible for all frames and does not dilute completely even with 1500 samples.
The scene attached shows the pattern every time I render it.

openCL Issues_Birch.7z
Here, with this scene, happens only some time: this makes the problem very hard to investigated. It may be related to variance clamping, can you check if it happens when variance clamping is disabled ? And if CPU/GPU hybrid rendering is disabled ?
What do you mean with "variance clamping"? The only clamping I know yet is Light Paths>Clamping.
For the following three tests I stitched clamping off.
Tested are CPU only, openCL only, openCL plus CPU. CPU does not show the strange patterns even with a few samples.
Animated GIF, please click to view
No-strange-effect,-CPU-path
No-strange-effect,-CPU-path
Strange-effect,-no-CPU-openCL-path
Strange-effect,-no-CPU-openCL-path
Strange-effect,-openCL,-CPU-path.
Strange-effect,-openCL,-CPU-path.
I have found another issue, it might be related to the one above. Again the patterns around the outer sphere do not appear on CPU only.
Tested are CPU hybrid, openCL path only Random, openCL hybrid Sobol. The pattern does also appear with openCL hybrid and Random.
Animated GIF, please click to view
Another-strange-effect,-CPU-hybrid,-Random
Another-strange-effect,-CPU-hybrid,-Random
Another-strange-effect,-openCL-just-path,-no-CPU,-Random
Another-strange-effect,-openCL-just-path,-no-CPU,-Random
Another-strange-effect,-openCL-hybrid,-Sobol
Another-strange-effect,-openCL-hybrid,-Sobol
And here is the scene containing the half Null Glossy sphere with Glass sphere, homogeneous volume, inside:
Strange Effect, openCL hybrid.7z
Strange Effect, openCL hybrid, Sphere in sphere
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B.Y.O.B.
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Re: openCL render issues: unknown pattern, sporadic white particles with Matte translucent

Post by B.Y.O.B. » Thu Oct 24, 2019 1:58 pm

FarbigeWelt wrote:
Thu Oct 24, 2019 9:16 am
What do you mean with "variance clamping"? The only clamping I know yet is Light Paths>Clamping.
They are the same thing, in BlendLuxCore it's just called "clamping" without the "variance".
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Dade
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Re: openCL render issues: unknown pattern, sporadic white particles with Matte translucent

Post by Dade » Fri Nov 01, 2019 1:43 pm

FarbigeWelt wrote:
Thu Oct 24, 2019 9:16 am
And here is the scene containing the half Null Glossy sphere with Glass sphere, homogeneous volume, inside:
Strange Effect, openCL hybrid.7z
It just work fine here. I will try if it is a Windows-only problem otherwise it is quite impossible to fix if I can not consistently replicate the problem.
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Re: openCL render issues: unknown pattern, sporadic white particles with Matte translucent

Post by kintuX » Sat Nov 02, 2019 5:36 am

FarbigeWelt wrote:
Thu Oct 24, 2019 9:16 am
I have found another issue, it might be related to the one above. Again the patterns around the outer sphere do not appear on CPU only.
Tested are CPU hybrid, openCL path only Random, openCL hybrid Sobol. The pattern does also appear with openCL hybrid and Random.
Animated GIF, please click to view
CPU-hybrid,-Random.gif
openCL-just-path,-no-CPU,-Random.gif
Strange-effect,-openCL-hybrid,-Sobol.gif
And here is the scene containing the half Null Glossy sphere with Glass sphere, homogeneous volume, inside:
Strange Effect, openCL hybrid.7z
Just rendered as posted... Looks fine here:
Strange Effect openCL hybrid.jpg
W10 (1809), Blender 2.81 beta; Hash 78bad368d12dB w/ BlendLuxCore daily 19919a2)
NVidia GPUs + TR CPU
Note: Disregard colour, i'm using ACES.

:? Could be your drivers...

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