Leica's legendary 50mm f/2 for M-mount — produced across multiple versions spanning decades of optical refinement.
The Leica Summicron-M 50mm f/2 is the standard-production version of Leica's 50mm rangefinder prime for the M-mount system — the classic double-Gauss formula in continuous production since 1979 (Version 5). Manual focus only — all Leica M-mount lenses are manual focus. At 242g and 39mm (E39) filter thread it is compact for an f/2 prime. Eight aperture blades. Minimum focus distance of 0.7m.
The optical design uses 6 elements in 4 groups (classic symmetrical double-Gauss design). Eight aperture blades. The 39mm (E39) filter thread is the standard Leica M-mount thread. At 242g the lens is lightweight. Minimum focus distance of 0.7m. Manual focus only — no AF. f/2 maximum aperture. Full-frame coverage on all Leica M-mount bodies.
The Summicron-M 50/2 double-Gauss formula provides the rendering characteristics that define the Leica M 50mm aesthetic: moderate wide-open glow that transitions to crisp definition by f/4, with smooth out-of-focus transitions from the 8-blade aperture. The lens is optically distinct from the APO-Summicron-M 50/2 ASPH (8 elements, aspherical, apochromatic) — the standard Summicron is the affordable rangefinder M 50mm option, not the APO.
On the used market the Leica Summicron-M 50mm f/2 is available at Leica prime pricing. Condition checks: E39 filter thread condition, focus ring smoothness through full range to 0.7m, and front element for marks. Confirm this is the standard Summicron-M 50/2, not the APO-Summicron-M 50/2 ASPH (which is a significantly more expensive lens). Compatible with all Leica M-mount bodies.