Attach a Canon 1100d to a Celestron C8 XLT OTA? lol

[asteele3]

I have bought the Canon EOS t-ring but I don't know size of the adaptor I need for it. Is it the 1.25" or the 2"? How do I tell?

[steppenwolf]

The Visual back on this telescope has a 1.25" eyepiece holder but I think you would be better off with a Celestron Camera adapter to screw into your camera's 'T' adapter.

[Cornelius Varley]

There are various ways to connect the camera to the telescope:

1. http://www.firstlightoptics.com/adaptors/celestron-sct-t-adapter.html. This screws into the visual back of the telescope and the t-ring is attached to it.

2. A 2" SCT adapter http://www.firstlightoptics.com/adaptors/baader-sct-to-2-inch-adapter.html and a 2" nosepiece http://www.firstlightoptics.com/adaptors/flo-2-inch-t-mount-camera-adapter.html.

Peter

[Priastro]

I am in the same planning, but my camera is a Nikon d7000. What I can understand it is fine to connect the camera to an C8 via an t2 adapter and an celestron camera adapter. But if I want to connect a barlow between I think that is not possible, and instead I need a converter to the diagonal 1.25 and then place the barlow between. Is that correct?

Martin

[Cornelius Varley]

I am in the same planning, but my camera is a Nikon d7000. What I can understand it is fine to connect the camera to an C8 via an t2 adapter and an celestron camera adapter. But if I want to connect a barlow between I think that is not possible, and instead I need a converter to the diagonal 1.25 and then place the barlow between. Is that correct?

Martin

It is generally not recommended to place a diagonal in the imaging path. A diagonal would reduce the amount of light reaching the camera and might degrade the image. If you look at my previous post you can see a better way of connecting a camera to a telescope with or without a barlow.

Peter

[Priastro]

The Celestron t-adapter fits to the rear cell oft the telescope and in the other end the t2 adapter or t-ring fits, then the dslr to the t2 what I can understand. The barlow is 1.25 or 2 ". Instead of a celestron t-adapter it should be a 1.25 or 2" to t2 adapter? I am total novice here.

Martin

[Cornelius Varley]

In my set up I use a SCT-2" adapter http://www.firstlightoptics.com/adaptors/baader-sct-to-2-inch-adapter.html and then either a 2" nosepiece connected to the t-ring or a 2" Powermate which can be attached directly to a t-ring. If you have a 1.25" barlow you can use a 2"-1.25" adapter http://www.firstlightoptics.com/adaptors/2-to-125-eyepiece-adaptor.html to change down to 1.25" and then a 1.25" nosepiece http://www.firstlightoptics.com/adaptors/flo-125-inch-t-mount-camera-adapter.html and then a t-ring.

Peter

[Priastro]

OK, for 2" powermate/barlow that is the solution. If I am going to use 1.25" powermate/barlow instead I could go for the 1.25" nosepiece inserted directly to the visual back, which is cheaper. Can there be focusing problems? Little of the topic, but are there benefits to choose a 2 " powermate/barlow insted of the 1.25 for dslr? Can there be vignetting?

Martin

[Cornelius Varley]

There shouldn't be any focussing problems. SCTd and Maks have a wide focussing range and I have never run into problems with this set-up, even when using a JMI crayford focuser instead of a SCT-2" adapter. You might get vignetting using a 1.25" nosepiece.

Peter

[Priastro]

OK, thank you.

Martin