GeraldW
Veteran Member
PDAF is generally an "open loop" process where the processor tells the lens to focus to such and such a point without rechecking the focus. it leads to front or back focus. Cameras that are basically CDAF may work both sensors to "close the loop" and check focus near final focus - I'm not at all sure about that. Although, I do know my Sony SLT-A57 achieved perfect focus with two lenses I had.
The ultimate test for that is to manually focus as well as possible, and then take the same scene with AF.
The ultimate test for that is to manually focus as well as possible, and then take the same scene with AF.