Mine oag is the orion, i don't use it much because it's so hard to find a guide star. I wish the'd put some sort of bigger mirror to increase the field of view. To me, a flip mirror with a central hole big enough to illuminate a 1 cm X 1 cm (~1/2 inch) chip would be ideal.
Thanks for checking them out guys.
dickbill, that's an interesting idea, a cassagrain OAG.
I had similar problems with the Meade OAG, in some configurations it would only illuminate half the guide camera chip. The pickoff prism in this TeleskopService OAG/flip is quite a bit larger and fully adjustable. I can set the prism as close to the imaging chip as possible.
It's also 360 degrees rotatable independant of the camera but so far I haven't needed to 'search' for guide stars. Once or twice I've just needed to offset the target framing a bit to get a guide star. I left the piggyback refractor in place with a DSIpro on it so if some target is missing guide stars in the OAG I'll just switch to the refractor.