Here's an image I did with my 400mm f/6.3 telephoto lens on piggybacked on the telescope.
It's three 3 minute exposures stacked @ ISO1600, 9 minutes total exposure time. I put a higher resolution version here
http://www.skylab.com.au/pmsa/ngc3372d.html
Clear Skies
Paul M
http://www.skylab.com.au/pmsa