All TG except for the background peak, which was output from Gaea in order to have a go at the snow node. I probably should have done some masking/combining within Gaea on that snow node for a little more realism, but I really haven't used it much. I'll eventually get to that.
As for the interior cloud lighting, the source lights really are a weird bird.
The extreme (or at least what appears to be extreme) settings you have to use in order for the light to illuminate the cloud interior are pretty wild. Great for Nebulae and space gas stuff, as has been illustrated in the super huge nebula thread here about a year ago. That guy's stuff is fabulous.
I did some roiling clouds/internal lighting flash animations for the show Legion a couple years ago, but I've never seen the show so I don't know if those elements were ever used by the Nuke guys. They came out awesome, though.
Whoa! Great render times and awesome cloudscape. Neat ititerations.
Wow, nice couple of renders!
I like the ones with the trees closer in the foreground and that last one most! Great!
Like them all! The night ones in particular.
I like these variations too, but to me it looks more like a volcanic eruption rather than normal clouds, because the big cloud is sitting on the ground on the horizon.