This is probably a really stupid question.
Why does it take so long to render out a volume to the same quality from what you see in the viewport.
Also is increasing pixel samples the only thing I need to achieve the same level of detail and how can I reduce the render times.

TIA
Juan

here's a pic

The similarity could be a testament to how sophisticated OpenGL display properties have gotten. But you'd probably start seeing a much more pronounced difference with more detailed, noisy, and intricate volumes.

You may have seen some of these resources for improving rendering performance already:

http://www.sidefx.com/docs/houdini12.5/render/tips [sidefx.com]
http://www.sidefx.com/docs/houdini12.5/render/volumes [sidefx.com]
http://vimeo.com/40300224 [vimeo.com]

The similarity could be a testament to how sophisticated OpenGL display properties have gotten

Must be great for video games.
Thanks for the links will check them out I just got a new graphics card and installed houdini 12.5 so I'm seeing vast improvements all round.

Juan

have you tried rendering in PBR?
what is your mantra options! can you post a file?

lari

Hey larikaram
Here's the file I messed around with some more stuff after I posted, there wasn't anything special to that setup just dropped a torus bumped up the columns/rows to about 50 hit the ‘cloud rig’ then bumped up pixel samples to about 30. Tried using both manta and PBR to see which looked better

For those interested there's a good post HERE
http://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&t=28226 [sidefx.com]
on how to make volumes look good
Juan

It just happens that in the particular case where:
1) you only have one light source,
2) the light source is far outside the volume,
3) the volume isn't between the view and the light,
4) the volume is highly opaque and diffuse, and
5) the view is far back from the detail of the volume,
there wouldn't be much visible difference. In many other cases, the difference can be quite pronounced, because the viewport is just doing volume splatting, whereas Mantra can do real ray marching.

Hopefully that clarifies things!

Hey ndickson Thanks for the help it's much appreciated.

Hopefully that clarifies things!

Yeah, in this case I did just about everything wrong oh well live and learn.
Thanks again
Juan

Nah, you didn't do anything wrong! You brought up quite relevant points, and I'm impressed by how fast and accurate volume splatting can be for dense clouds, which is quite handy. I only meant to outline some other cases that don't work as well.