Nikon 500mm f:4 D EDNikon F mount Lens is very sharp but the AF doesn't work. Manual focus works to a certain extent but it's also defective. LENS IS BEING SOLD AS A BROKEN - NO RETURNS There is a possibility that the front of the lens has been taken off to be cleaned in the past as there is a scratch on the plastic inside the lens- there is also a dent on the front of the lens. I used the lens with my D850 and I was able to take pictures and focus with it in Manual Focus but again the manual focus has a really long travel that's why I believe it's also defective.