In the middle of Sydney your not gunna be able to see many DSO's anyways from all the light pollution. Your really limited to planets,bright nebulas, and star clusters. You don't need over 16" telescope to view them. I have a Celestron c14 and im south of Sydney. Visually i can only see planets,bright nebulas, bright galaxies and star clusters. I have found that you cant even view the bright galaxies unless you have really good night (which is rare in Sydney)
