In my case (with a 10" Newt GSO f4) there is a 2" tube that fits into the focuser that has the 1.5" eyepiece attached to it. Take it all out and get a 2" T piece adaptor for your camera. I put some threads on here about it. It brings the DSLR nearer the focus point and worked with mine.
Just stick it on the camera and go straight into the 'hole' in the tube.
Will look around for the website I got mine from
http://www.cncsupplyinc.com/index.htm?all_canon.htm
This for a canon, they have others and it's shorter that attaching a T piece with a standard 1.25" nose piece then bunging that on a scope's 1.25" eye piece. Worked for my GSO.
Good luck
Graham