While it would discard it if you ONLY used the main alpha image, you could still add that in a layer n photoshop, and adjust another layer using the background render as well.

I usually use a gradiant of some kind in my renders in the background, but almost alwaysdo them in photoshop, just because it's what I've used for years on end.

Just looking for poser centric options, and thinking about options and possibilites.

Way too many people take way too many things way too seriously.