Ok, now I'm sure that my scope has a small (nearly) focusing astigmatism. Well, in principle it helps focussing, even though it p.... me off. After more than a months I went out yesterday into the cold (around -8 degrees centigrade) for three hours. Well, handling the stuff was really hard, and all I got was a ten minute picture of M42 (again). But hey, its great after two months of clouds.