50 Things Photographers Need to Know About Focus

25. MIRRORLESS VERSUS DSLR LENSES

THE SHIFT FROM phase detection focusing to contrast detection focusing means that the lens on a mirrorless camera functions differently than the lens on a DSLR.

Fly-by-Wire Technique

Traditional autofocus lenses usually featured a mechanical linkage between the focus ring and the glass elements, but mirrorless lenses require focus motors that can move quickly in small increments, reverse direction, and stop on a dime. The motors that perform these actions connect the focus ring to the lens elements using a fly-by-wire technique. The mechanical movement of the focus ring is electronically calculated and transmitted ...