CCD to Telescope connection

[Phillyo]

So after much thinking, umming and arrring, speaking to people on this and other forums I have decided to go with a QSI 583wsg to use with my Megrez 72 and maybe a slightly longer focal length in the future. Initially for nice wide field views but maybe a little longer in the future...we'll see. I'm also thinking of attaching some of my camera lenses to it but that's a discussion for another day.

My question is, how do I connect it all together? I know it may sound silly but as I've never had or seen a CCD before I don't know how they attach to the scope. I have a set of Ha, OIII and SII filters (1.25") that will fit nicely inside the CCD and will be getting a guide scope in the near future, but at the moment when connecting my DSLR to the telescope it goes...

DSLR -> T-Mount -> WO FF/FR 6 -> Telescope 2" connection.

How do I connect the CCD? I'm guessing I'll still need to use the FF/FR for round stars at the corners but how do I connect it to the CCD? Does it just screw on where the T-Mount would usually be? What about the focal distance?

Thank you,
Phil.

[Zakalwe]

CCD cameras will have a female T2 thread on the front of them. You will shortly amass a large collection of T2 adapters, converters, spacers and tubes, half of which will end up permanently stuck together and all of which will be ridiculously expensive for what they are.

The field flattener that you will need will normally have a male T2 thread on the rear. This will mate up to the filterwheel or camera. Some focusers will also be threaded, which means that the complete optical train is threaded together. I think that this is the best solution, but the most common practive is to hold the field-flattener/reducer in the focus draw-tube with the normal thumbscrews.

[Phillyo]

Awesome, thank you.

[wuthton]

You will shortly amass a large collection of T2 adapters, converters, spacers and tubes, half of which will end up permanently stuck together and all of which will be ridiculously expensive for what they are.

It's so depressing spending £30 on a tiny slither of threaded steel. Being over a barrel springs to mind.

[Uranium235]

Zakalwe, on 05 Sept 2014 - 10:05 AM, said:Zakalwe, on 05 Sept 2014 - 10:05 AM, said:

You will shortly amass a large collection of T2 adapters, converters, spacers and tubes, half of which will end up permanently stuck together and all of which will be ridiculously expensive for what they are.

Lol... never a truer word spoken. I think I must have evey possible combination of T2 and M48 adaptors now!

As for them being stuck together, if the rubber gloves dont work - then I end up taking a hacksaw to them and cut two grooves so I can get a tool in there for more of a lever action.The one I dont like is where the adaptor is cold welded to your camera nosepiece, in that situation you need to be very careful indeed.

[Zakalwe]

As for them being stuck together, if the rubber gloves dont work - then I end up taking a hacksaw to them and cut two grooves so I can get a tool in there for more of a lever action.The one I dont like is where the adaptor is cold welded to your camera nosepiece, in that situation you need to be very careful indeed.

I've had that one. Brought me right out in a cold sweat trying to remove it.

Hateful blooming things!

[Phillyo]

Filling me with confidence here guys, thanks ;-)

[Joel Shepherd]

Tip from the bike shop mechanic: a little bit of medium weight grease on threads will allow you to tighten without fear of seizing and will go a long way to prevent cold-welding, even in damp conditions. Obviously, don't over-do it and carefully wipe away any excess so it doesn't attract dirt or get all over your optics.