An example of using an image mapped onto an alpha plane. The sky and clouds are from a picture I took in my own backyard, then added onto an alpha plane and put in the background. 20 minute render time at 1600 X 1200.
Many thanks to =relhom for turning me onto this idea, and here is a link to the very simple yet effective technique by Thomas Krahn: [link]
D'oh - and I was just about to ask "how did you make such realistic Vue clouds?" only to find out it was a photo oh well, I find myself postworking skies more and more - often looks more real and increases render speed
I find Vue has very realistic skies, as long as you get into the atmosphere editor and play around a bit. Here's one along the same lines as this one: [link] That is pure Vue sky, but it rendered about ten times as long as this one. I don't like postworking at all, and I never do it on anything.