One render layer with background image and one with transparent background I made an animation with an environment texture in the background and I would like to have one render layer with only the background image and another render layer with all the objects on a transparent background.

I tried to uncheck the "Use Environment" on the objects render layer, but this rendered the objects on a black background (not transparent). On the other side if I set the film to transparent in the render settings, then the objects are on a transparent background (as I want), but the background layer is empty. 

I use Cycles for rendering.
Enable Transparent on the Film section and enable environment on your render passes. The background environment will be avalible by connecting the environment socket.