A zoom finder drive mechanism, driven only when taking a picture. When a
lens barrel is in a collapsed position, the cam-follower pin of a rotary
barrel does not abut at an end of a protrusion of a finder cam barrel
such that a first and second movable finder lenses are idle. When taking
a picture, the cam-follower of the rotary barrel is abutted at the end of
the protrusion of the finder cam barrel such that the first and second
movable finder lenses are driven.