Connecting a QHY8 to NS8

[Helen]

I was wondering how people connect their QHY8s to the scope. I've been having problems with egg shaped stars and trailing and so am eliminating all options (I haven't been guiding, so no flexure issues - yet!). the most obvious cause for concern at the moment is how tightly the camera is held in the scope. I've been using a 1 1/4 nosepiece (borrowed from the H9), but the nosepiece has an undercut, and my barrel reducer has a compression ring, and so it doesn't seem to hold securely (or squarely). So I assume I'd be better with a direct attachment. Any advice please?

Thanks

Helen

[steve51450]

hi Helen

what dovetail have you got on the ns8 because you can still get flex even if you are not guiding, also a 11/4 nose piece is way to small for a qhy8 you will need a 2" nosepiece otherwise you will get severe vignetting. Also make sure your rings etc are nice and tight

[Helen]

Thanks Steve. I need a new nosepiece then! As far as the scope goes, its still in its fork arms so there isn't a dovetail. The counterweight position might have added to the problems though (and I gave up for the night when the weight came off in my hand when trying to adjust it - a bit of a shock in the early hours of the morning!). I think I've sorted the balance out now though. So I'll try again tonight (with and without guiding as a test).

Helen

[Beyond_Vision]

Steve is right I would use 2 inch fitting to the scope as the 1 1/4" would cause vignetting.

Regards

Kevin

[Helen]

Good news. I've located a 2 inch nose piece (again taken from the H9!) and have attached the camera to the scope with it - and its really solid . Just need it to get dark now

Helen

[MartinB]

A 2" nose piece should be ok Helen but a screw fit arrangement is a more secure, rigid arrangement and less likely to produce collimation problems with the chip. Have a word with someone like Bern or Ian King to get the right arrangment of adaptors. Basically you want a female SCT to male T thread. You also need a ring with a T thread (I'm sure there is a proper name for this!) that screws onto the male T thread of the adaptor before you screw in your camera. Set the camera to the position you want then lock it very firmly with the ring. Rotation of the camera is easily achieved by loosening the ring. The downside is that you need to refocus whenever you rotate, but I do that anyway because I never trust things to stay in focus after rotation even with my FSQ.

Hope that makes sense

[Helen]

Thanks Martin! I check out my adapters and see what I've got...

Helen