Clouds using phoenix

[CCX]

Hi,
There have been couple of posts already on creating clouds with Phoenix,
based on those info and some fumefx tutorials I am trying to simulate clouds using phoenix similar to the ref image.
I have a base geometry to emit smoke from.
These are the settings i have used :
Temperature disabled in the source.
In the simulator,
Units : Meters, Total Number of cells : 14M
Smoke Dissipation : 0.4
Vorticity : 0.1
Conservation : buffered, Quality: 20
Advection: Multi- Pass.
Smoke color : simplecolor
Density : 0.12.

Added Phoenix Turbulance node with
size 2.0 and Multiplier 5.0.

I simulated for 20 frames and rendered the last frame.
As you can see surely I am missing something here.
It am not able to achieve the whispy details at the edges and
the over all noise inside the clouds.
Any suggestions on how i can improve on this.

Thanks in Advance.

[Ivaylo Katev]

i really doubt that with this approach you can achieve the reference image.
the clouds have their shape from the all scale turbulences, large, middle and small. if you try to fake the large and middle scale turbulences replacing them with a source geometry, using the simulation only for the fine surface turbulences, that is the result.
we really have to make a tutorial, because this is frequently asked question, but for now my suggestion is to create a source plane with mapped discharge, and to emit smoke, render only the upper part of the grid with the caps (use gizmo to cut the lower part)

[Svetlin.Nikolov]

Hello,

Some more ideas:

From your shot it looks like the turbulence wasn't strong enough to kick in visible. Try to increase the scale of the turbulence and the power.

Also, add some noise on the PHXSource object, there is an option there - this way you will get more interesting base shapes, instead of the spheres that occur right now.

Another thing you can do is to use render-time displacement - in the Rendering panel, enable Displacement and use Surface or Gradient driven with a monochrome texture, or Vector with a color texture. For the first two modes you have to set the Surface to Smoke and the Surface level to 0.5.

[CCX]

Thanks Ivaylo and Svetlin ,
That helped quite a bit. I tweaked based on your suggestions.
So far it looks promising.I will have to tweak a lot more on the shapes part as well.
I will also try with the plane with mapped discharge for the further away clouds.

[flipbook]

Dont know if its any help but when I did this in FumeFX, I had two versions of the cloud. One was thick similar to your first cloud and the other was whispy similar to your new one Composited them together to get a nice medium.

http://www.flipbookstudio.co.uk/brot...europe-clouds/

I assume you could do something similar with Phoenix. The above is probably a little too thick for what you're after but it could work

[CCX]

Hey Flipbook,
Thanks for the tip, those clouds looks cool .. I will give a shot and see how it comes up

[CCX]

Regarding the mapped discharge, in Maya i have tried the noise textures but only the marble texture seemed to work as modifier.
Is this the same case with you guys too ?

[wxyz]

Here's an attempt

[CCX]

That looks cool 'wxyz' thanks for the post, How did you achieve the fluffyness ?
and oh regarding the noise textures, for mapped discharge.. 'Alpha is luminance' have to be checked to take effect.
Now all the noise textures are working.

[wxyz]

https://vimeo.com/134637864
animated noise plus VRayVolumeGrids
about 13 seconds per frame at 1920 HD w/o gi.