I've usually gone with 4000 x 2000, output from Vue, as a "happy" medium. Takes about a day usually, on my kit, at "broadcast" resolution. Perfectly adequate for cloudscapes unless you're really zooming in on a portion, in which case, do you actually need the whole thing?

12000 x 6000 was the max I've tried, and it took a week... well, six days. It was in the centre of a model of the Louvre though, so wasn't just sky that was being rendered.

That was rendering using the batch renderer in Vue though, which is slower, but doesn't consume all the system resource. I didn't want my imac to melt... and I was still able to use it for most other stuff while the render was running.

After something BB suggested / mentioned, next image I try this for, I'm planning to do it differently... I will do two Vue renders I think.

EDIT: Yup... in that thread you linked to, indeed!

A 4000 x 2000 (or potentially smaller) spherical panorama, at "final" resolution, to serve the IDL and distant reflections from behind the camera.

Then a render of just the Vue scene that I want in front of the camera, a little more panoramic than will be needed for the angle of the camera in my Poser scene. I'll put this on a slightly concave, rectangular prop, behind the Poser scene.

I could have done this with the Louvre example... probably could have got a better result.

I'm generally not using the Vue render to represent anything too close to the camera... using poser sets for that.

Cheers

EDIT: ...also there are some Vue rendered panoramas in my gallery, and the higher res versions can be downloaded here:

http://bananas.monkeycloud.net/panoramas/beta/