Welp I just bought half of the stuff in this comment I didn ' t have <| sep |> Removed . We are getting rid of the pst post . Not really the place . But try rpoppytea if you have not heard of it . Good luck . <| sep |> Well , there is AF Enable and AF Cancel when using BBF . AFE means that the AF is enabled when you are pressing the button . AFC means that when you half press the shutter , it focuses as normal , until you press the button on the back to stop it from focusing any more . The benefit of the first is that you only focus when you want to , and you aren ' t waiting for focus confirmation . The benefit of the second is that the shutter button works as most people expect and you only stop AF if you want to recompose , or you want to take a burst and not wait for AF between shots .