Thanks stewer, I already reduced the size of the Mil Dragon Maps. Floor and Walls are not casting shadows due to the selfshadowing problem we discussed already in another thread. It renders fine now (approx. 50 minutes on a AMD 2100+) at production level. Added also DOF and it's gettin' better and better. Thanks to all your help I have a feeling now, where I can tune FireFly to get results. There are a lot of options. Thanks - Walter