Autofocus cameras

Autofocus drive

— the presence in the camera of a built-in autofocus drive of the "screwdriver" type.

This function is relevant only for interchangeable optics (see "Direction"). Her idea is to place the autofocus motor not in the lens, but in the camera body. Thus, optics for a “screwdriver” are lighter and more inexpensive than similar lenses with their own motors. However, when mounted on a camera without a built-in drive, autofocus in such a lens becomes unavailable. But the presence of a “screwdriver” in the camera, usually, does not prevent the use of “motorized” lenses with it.