Is there any way to exclude stars from the render layers?
Just turn them off.
If you want them as a separate pass, just create a new scene just for stars and link your camera from the main scene to the stars scene. Then in the compositor you can bring in that render layer and composite as you wish.
Ah, good idea. Thanks!
No need to create a new scene though since the Stars setting isn’t independent from scene to scene. Seems like it should be. Oh well.