hi alan,
take a look at this page for some information
http://www.iceinspace.com.au/63-201-0-0-1-0.html
for a 600d you will probably want to go prime focus, but first what type of dob do you have? some struggle to reach focus with a camera. usually you would take the lens attach
http://www.bintel.com.au/Astrophotog...oductview.aspx
and then something like
http://www.bintel.com.au/Astrophotog...oductview.aspx to attach to the 2" focuser.
cheers
russ