Question: what is afma in photography?
Answer: Autofocus microadjustment (AFMA) is a procedure that allows a user to correct for small errors of front- or back-focusing. It is a feature that is present only on certain models of Canon dSLRs (currently, the 50D, 7D, 5D Mark II, 1D Mark III, 1D Mark IV, 1Ds Mark III, and 1D X).