I don't know if anyone else noticed this but all the features of Hogwarts have seemed to have just got up and walked to wherever they want.Like the whomping willow.in hp2 it was right by the castle but now its a long trek to get down to even get a glimpse of it.The dementors looked as if it was just a balloon head with a cloak draped over.i thought they would look at least like a 12 foot tall man in a cloak.But a dead rotten one.and the scene with all the dementors and the patronus.The dementors are supposed to glide over the lake's surface but they fly about like idiots and the patronus was supposed to gallop from where harry cast it but all it did was shine that retarded light.the directors probably thought that we wouldn't notice if they didn't take the time out to do things properly but they were mistaken.