Werner Ziemerink
Yes, I'm getting allot more crashes with Build 392. No image output.

It's strange, I was able to get a render out at 256 before, but I had a different image plane configuration. I'm trying one without them to see if that was it.

Edit:
it would be nice if there was a traceback when karma crashed. Right now, it just looks like it finished without producing output. If you turn on alf progress, you can see it only gets to X% and not 100.

Edit2:
disabling aovs did not help

I'm rendering the scene you provided in a loop, but so far I'm unable to reproduce the crash. may I ask what command line arguments you're passing into husk?

@Werner: did you mean build 393?

dlee
I'm rendering the scene you provided in a loop, but so far I'm unable to reproduce the crash. may I ask what command line arguments you're passing into husk?

@Werner: did you mean build 393?

I'm just hitting the render to disk button on the karma node. It gets to 70ish percent every time and then stops rendering. I'm on Windows, using the production build 391.

The previous builds 391 and 392 was super buggy for me.

First try in 939 and I could get a render out by doing the same as jsmack.
Render to disk, with Variance set to Uniform, and 256 samples. Nothing else.
Doing this test from home on Apprentice, so I can't push the render size any higher, to test.

Ok i must be doing something wrong

Love the tests, expecially the emily one. I did a test with emily and it just looks noisy as hell. This is with the random walk. Please ignore the groom it is by no means finished.





My settings were around 265, uniform light sampling & pixel oracle. My light sampling was at 1, is that what needs to be increased?

This is about an hours long render. The hair rendered super quickly.

Cheers for anyone that can help

Yeah, I'm not sure what happened to Random Walk SSS in Karma. I can't get clean renders out anymore.
It is noisy AF and takes way too long to render. Definitely not the way to go for me.

Werner Ziemerink
Yeah, I'm not sure what happened to Random Walk SSS in Karma. I can't get clean renders out anymore.
It is noisy AF and takes way too long to render. Definitely not the way to go for me.

Are you able to get the base color to do much with random walk? It seems like it doesn't matter how dark I make it, I can't get it to look like a material with a high extinction coefficient.

Do you find the random walk noisier/taking longer to resolve than full sss in karma? They seemed about the same to me.

Werner Ziemerink
Yeah, I'm not sure what happened to Random Walk SSS in Karma. I can't get clean renders out anymore.
It is noisy AF and takes way too long to render. Definitely not the way to go for me.

I have even turned off SSS and displacement… just having a model with a texture and 1 single light with over 512 samples still produces noisy renders.

abvfx

Werner Ziemerink
Yeah, I'm not sure what happened to Random Walk SSS in Karma. I can't get clean renders out anymore.
It is noisy AF and takes way too long to render. Definitely not the way to go for me.

I have even turned off SSS and displacement… just having a model with a texture and 1 single light with over 512 samples still produces noisy renders.

Strange, a simple scene with a diffuse material and small light should be fairly noise free at 128 samples, as long as variance is turned down from the default 0.05 to 0.01


Edit: I tried increasing SSS samples to 16, but the results are pretty broken.


Increasing total samples is the only way to improve sss, but even 512 isn't as clear as I hoped for.


Using 512 fixed samples takes far more time, but very little changes except in the shadows.

Yikes. Overriding SSS Sample count seem severely broken - investigating. The other noise issues that remain despite high camera sample count is due to known issue with RNG in 18.0.

The only thing that seems to make the situation better is rendering to disk.

That provides a slightly better result (for some reason)

jsmack
Strange, a simple scene with a diffuse material and small light should be fairly noise free at 128 samples, as long as variance is turned down from the default 0.05 to 0.01

Yea with a colour texture it has tons of noise. If it's one colour it's fine.


I will keep testing though

abvfx
The only thing that seems to make the situation better is rendering to disk.

That provides a slightly better result (for some reason)

Rendering to disk uses different sampling with karma.

Upcoming daily build (18.0.469) will have reduced noise in offline rendering (for random walk SSS) and fix the ugly tiling artifacts when adjusting SSS Samples parameter.

Also

Houdini 18.0.473

• Fixed a bug in karma where PBR SSS would appear brighter than expected in bsdf-centric lighting.
  
• Fixed a bug in karma where setting SSS limit greater than 0 would either cause PBR SSS to pick up indirect bounce from wrong location, or Random Walk SSS to mix in diffuse bounce and appear overly bright.
  
• Also fixed indirect bounce from non-SSS BSDFs having incorrect amount of contribution in a compound BSDF with SSS (most noticeable under IPR)
  

I will be testing all of these. Thanks for all your hard work.