couldn't get answer else where, so decided to try with this poll.
pls note :
1) this is a poll for those regular bird shooter during the film days, if you started photography with digital and have no experience in shooting birds using film cameras, pls do not vote here.
2) if you shoot with TC, than pls select 400mm if you had use
300mm + 1.4x TC = 420mm
3) pls select 800mm if you had use
400mm + 2x TC = 800mm
pls note i am not trying to make people angry with (1), but i only want to make sure in the end, i get the correct feedback on the common focal used to shoot bird during the film age.