Cheers Suavi. I see what you mean now, hadn't really thought about that. I've only got a small Sony sensor and that's never been a factor for me, but that's probably much more of an issue for those with APS-C sized sensors and larger formats.
Here's a link to the thread I was talking about
:
http://www.cloudynights.com/topic/42.../#entry5489591
I actually don't know whether the QHY does hardware binning or software, so there's that as well.
So while the QHY might technically be more sensitive, practically it might work out in favour of the Lodestar, especially in NIR where the Lodestar is going to have a significant advantage.
Thing is though, I'm not convinced that it'll make the difference between detecting no stars and detecting them well enough to guide on.
Just to clarify, are you suggesting that you don't have to rotate your OAG at all to find a guidestar? I always find one, I just have to rotate to do so, and sometimes when I do a meridian flip, I lose it.