I was trying to use 640 X 480 @ about f/40 - 45.
I haven't done the complete maths but thats allowing for 2X mag each even though technically thats not the correct mag due to image placement in each barlow and then projected onto the Toucam chip (probably closeer to 6X).
At the moment I'm trying to work out a way to attach my ToUcam to my meade variable tele-extender containing a 20mm eyepiece to up the f/ration to around f/50 or more without using a barlow to keep lense elements to a minimun. Haven't quite worked it out yet
I'll drop the resolution back and bit and see how I go.
BTW Welcome Back
Hope you had a great holiday!