I have an 200mm (8 inch) scope with 1200mm focal length - a good large but still portable size
The submillimeter emission is interesting, Im not sure of its exact nature but it could be a secondary reaction between some material spewed away from the black hole. The models we have for these situations are still pretty basic and dont even explain fully what is going on in our galaxy yet. So there is still a few more breakthroughs to be made yet.