The first M with TTL metering — 1971's bigger, bolder, long-misunderstood M.
The 1971 Leica M5 was the first M body with through-the-lens metering, using a CdS cell on a swinging arm that reads the frame centre and retracts before the shutter fires.
It is also the largest departure the M line ever made: a taller, wider body with a shutter-speed dial that overhangs the front plate so speeds can be changed with the camera at the eye, plus match-needle readouts in the finder.
Its significance is as the M line's controversial chapter: buyers of the era stayed with the M4, production ended in 1975, and the compact CL took over TTL duties, but the M5's metering and handling have since earned it a dedicated following and steady collector interest.
Used buying centres on the meter: the swinging-arm CdS cell and its resistor track age poorly, so confirm the needle responds smoothly across speeds. Early two-lug bodies hang vertically; the later three-lug revision carries conventionally. Deep-mount collapsible lenses must not be collapsed on an M5.