Maybe one of these might help Guy. Made by Nikon for the CIA and such sneeky beeky organisations.1200mm-1600mm Comes with its own trailor I believe
Top marks Guy for the tips and guidance. One good thing about digital though, a large Raw Image can be crop quit succesfully to get a good picture I tried this out at Mallory with my f2.8 200mm, giving me an effective 340mm lens on the D200 digital camera which does help to get into the action.