You be amazed what results a modded DSLR can yield.
Instead of spendings loads of money on a dedicated astro camera, why not just image with your dslr for a while until you feel that you cannot achieve what you want, then move to a dedicated CCD or CMOS astro camera.
When for many years imaging with a DSLR the only thing I regretted was my DSLR did not have cooling. Otherwise I would have not bothered moving to a cooled camera.
With your canon I would use a capture software like BackyardEos, much simpler to use then APT in my opinion. Especially if your a new comer to imaging.