Thanks guys for the nice comments. Paul I am using an FSQ 106 with reducer which gives me 386 mm at F3.6. The camera is a Starlight Xpress H16 with a 2048 x 2048 chip. Not sure exactly what the field of view is. BTW, general question, if you get on this Forum and see comments directed to you is there a way to respond directly or do you have to do it via email like this? Thanks Albert