It depends on where you're observing from. Back in 1959 I saw all the Messier objects from my back yard in suburban Montreal with an 8" reflector, but that was before light pollution became all pervasive. By the early years of this century, I could only see a few dozen Messiers from my back yard in suburban Toronto with the same scope. Nowadays I live in the country, and i can see all the Messiers easily with a 6" scope.
