Guys, just playing around with some fluids stuff and trying to achieve a pyroclastic flow effect. but have some questions for the “pros” out there.

http://www.vimeo.com/26098100 [vimeo.com]

, BUT my question is what is causing this noisey artifact ( you can especially see it near the base and the “leading edge” of the plume).
Here is some info to help debug:

1. Low rez is 100x100x100 uprez is 500x500x500
2. I am using the pyro shader, I am using a noise modifier in the color channel but even with that off I get the strange artifact.
3. I tried various settings for the turbulence in the uprez but still getting the artifact.
4. I tried a version with using the billoweysmoke shader, but if you look carefully you can see the same artifact, its just less apparent because the details are softer.

http://www.vimeo.com/26037278 [vimeo.com]

5. To save on disk space, I only exported density field to the highrez cache. Could that be causing issues?

also: the Pyro shader is SOOOO slow… why is that.. any optimization tricks? (buy a faster computer is not an acceptable answer) …. makes me pretty sad.

I also checked to see if its the depth map shadows, the rat files look clean but who knows. Im using 2 spots, both shadow.

Also tried different volume filters..nothing seems to kill it.

Double Post. I responded on the OdForce forums.

alright.. we'll take it over to odforce. Thanks.