I have installed a dish myself (Globecast), and I get a picture which seems very good (projected onto 76" screen), but I wonder could it look even better since the quality varies between around 45 at the low end, to 60 at the upper end and seems mostly to be around 52-56? Signal strength is always high - around 92.
The mast is not perfectly vertical. But I'm quite sure that I've got the "effective" elev and azimuth right, because moving the dish just a fraction in either elev or azi from where the dish now points sees a huge drop in quality.
The only variable I haven't monkeyed with is the skew, which is set at 114 degrees. Because the mast is slightly off from true plumb, the skew is likely to be a little wrong. But will a few degrees here or there may a difference? The reason I haven't messed with the skew is simple - it's quite a bit of hassle to do this with the
Globecast dish. Before attempting, I want to see whether it will be worthwhile, especially since the picture/sound are already pretty good.