DSLR to telescope

[Kenny]

I'm looking into what 'fittings' I would need to connect my Canon 450D to a telescope, any telescope, for example 8" Dob, 6" Newt or the OAS Coronado.

I quote from Carole's website:

You will also need some means of attaching your DSLR to your telescope.  You will need a T Ring (which fixes to the DSLR) and a T adapter which has a 2" nosepiece to fit into the telescope.  You will get better results if you use a flattener instead of a T adapter, and these are designed for specific telescopes, they flatten the field and the distance from sensor to point of entry to drawtube is vital to getting a nice flat field and nicely shaped stars into all the corners.

I only vaguely understand this, not enough to make a purchase, and don't know whether / why 2" is required rather than 1.25".

Grateful for your words of wisdom.

[MarkH]

Kenny most scopes have a 2" threaded connection point for accessories which is a standard thread. If you take your slr to somewhere like telescope house they stock "T" mount tubes, just make sure it fits your slr and its all you need.

[Carole]

Kenny, the DSLR will require a 2" nose piece otherwise you will get a tunnel vision effect.

Carole

[Kenny]

Thanks. The Dob and Newt support 1.25" and 2" but I don't think the Coronado does.

[MarkH]

My lx 90 has a 2" connector then an adaptor down to a 1 1/4" diagonal.

[Carole]

With the Coronado you will have to use a step down adapter if that's the case, not 100% ideal. 

Having said that I tried to image with a DSLR and the society Coronado once and it didn't produce anything except a bright red blob.  You'd be much better using a webcam with the Coronado.  They say a mono camera is actually best for solar, you can re-colorize it afterwards.

Carole

[The Thing]

My lx 90 has a 2" connector then an adaptor down to a 1 1/4" diagonal.

The thread on the back of an SCT type scope is not 2" filter type thread, it is 24tpi. But it is a 'standard' for the back of small to mid size SCTs so getting adaptors for t-mounts, diagonals and 2" push fittings is easy. It's a bit of a minefield and you end up with a large collection of this-to-that adaptors!
This is informative...
http://www.iceinspace.com.au/forum/archive/index.php/t-70937.html

[The Thing]

With the Coronado you will have to use a step down adapter if that's the case, not 100% ideal. 

Having said that I tried to image with a DSLR and the society Coronado once and it didn't produce anything except a bright red blob.  You'd be much better using a webcam with the Coronado.  They say a mono camera is actually best for solar, you can re-colorize it afterwards.

Carole

I think you need some sort of extension tube to obtain focus with a camera on a Coronado. hence why you only got a red blob.

[The Thing]

Thanks. The Dob and Newt support 1.25" and 2" but I don't think the Coronado does.

For your DSLR you will need a DSLR to t-thread adaptor and a t-mount to 1.25" or 2" (if both scopes support 2" EPs) adaptor. You probably have a 1.25" to 2" eyepiece adaptor.