Alpha as background? (animation)

Can you set the background (world) to be alpha in an animation? Thanks!

it is by default. the codec has to support the alpha channel. which QT and PNG do…see wiki on this FAQ, render format topic.

if u just want it to render without the world option just change it in the in the render panels.see attached image.

hope this helps…

you go to the render settings and hit the “premul” button.
Now the background is alpha.
But only QT and PNG can export that alpha background.
I usually go with PNG.