How to fit filter for prime fous photography?

[ThomasBR]

Hello, I need some help on how to fit filters for astrophotography. I have a skywatcher explorer 200p (a newt) with 'direct camera connection' feature. I also have a Canon EOS 500D and an appropiate T-ring. I can fit the camera on prime focus and take pictures with no problem.

I have bought a LP filter and OIII filter from FLO (both 1.25") and they are good for viewing (fits the thread on the EPs) but how do I use these for photography?

The T-ring skrews onto where the 1.25" drawtube would go except that the T-ring goes on the outside and the drawtube on the inside. The T-ring and the apator on which is fits are too big for the 1.25" and as far as I remember there is no thread for 2" filters. I have also bought a T-adaptor which goes into the 1.25" drawtube, it is threaded for 1.25" filters but when I use it I cannot reach focus (to little back focus). So, now I dont know what to do. Can anyone help?

Kind regars

Thomas

[Stephen]

As you've worked out, you can't use the filters in this configuration.

The easiest option would be to obtain clip in filters that go in the body of the camera.

The other options are to buy a low profile focuser (so you can use a 2" t-threaded nosepiece with a filter thread) or to move the primary mirror up the tube.

[ThomasBR]

Thanks for the advice Kh3ldar.

I think thet maybe if I could get a shorter eyepieceholder it could do the trick but I cant find it on the Net.

[Stephen]

Thanks for the advice Kh3ldar.

I think thet maybe if I could get a shorter eyepieceholder it could do the trick but I cant find it on the Net.

If you have the standard 200P focuser, nothing works apart from direct t-thread connection (There just isn't enough inwards movement!)

Another option is to use a Barlow - this moves the focal point out.