A telescope isnt needed for a majority of photos you see of the sky.
And there are connectors to hook up my camera to a telescope (its called digiscoping
) but if you have a standard 50mm lens, a 10minute exposure, and a tripod. you can get cracking star trail pictures.
Oh... and a 4.5 inch reflector is plenty for getting photos of stellar objects
8inches is frowned upon mainly because itll be too big and cumbersome for anyone to actually be arsed to go out with it.
You can also get mirror lenses for SLRs that can have insane focal lengths (500mm+) but have the same size lens as the 50mm
Was looking at them today, cost about £80 for em... as opposed to a couple of hundred for the 500mm.