If taking photos of aircraft with propellors, again'll allow a slow enought shutter speeed to show propellor blur - probably 1/500 down would give a balance between slowly enough to show some blur in the propellers and then enough and into being truely crisp aircraft.
If taking photos of aircraft with propellors, again allow a slow enough shutter speeed to show propellor blur - probably 1/500 or slower would give a balance between slow enough to show some blur in the propellors and fast enough to be reasonably crisp aircraft.