SW Esprit 100 with a 2.5 X Powermate. Aproximate focal length 1375mm, focal ratio about f 14. M83- 12 x 150 secs, M104 9 x 150 secs both guided using PHD2 on an HEQ5pro mount. Shot with a modded Canon 550d, UVIR cut filter at 1600 iso. Bortle 6 skies.
Just a test I did last night to see if this was possible. Results are encouraging.