Hey guys, I have been struggling with this for about two days, I have modelled a car and I am now trying to composite it into a scene, the only problem is that I can't seem to get the shadows to work. I have used the useBackground shader but this leaves a black plane in the render and nothing in the alpha channel. I really dont get why because it has worked before when i have tried this, I am using IBL with mental ray and ray trace on. Can you guys help at all, I can PM the scene file if that helps Thanks Paul