Thanks dave. The MR sun & sky setup is ok. Without DOF the shadow edges are fine. When I enable DOF, the edges around the out of focus objects appear grainy. The only way so far that I have found to kind of eliminate it is to up the min/max sample levels under Raytrace/Scanline Quality section at the expense of render time. Are these the settings I'm supposed to change? I know some people prefer to use depth maps to do DOF in post but I want to try both methods and compare the results.