SOM Berthiot Flor 50mm f/1.5

SOM Berthiot Flor 50mm f/1.5

The Flor 50mm f/1.5 is an exceptionally rare SOM Berthiot normal lens documented in a rangefinder-coupled Leica thread mount. Its substantial brass construction, polished chrome finish and early coated optics place it among the specialist fast lenses of the 1940s.

Optical qualities

Rendering

The f/1.5 maximum aperture allows shallow depth of field and low-light use. Surviving examples can show the lower contrast and flare sensitivity associated with early coatings, but dependable factory documentation for the optical formula has not been located. Element and group counts are therefore left unspecified.

Handling

The original LTM barrel is rangefinder-coupled for direct focusing on compatible screw-mount cameras. Verified figures for minimum focus, filter size, dimensions and weight are not available from the surviving auction documentation, so those fields remain blank.

History

Development and Launch

A documented Leica M39 example dates from the 1940s and combines a heavy brass barrel with a shiny chrome finish. The lens belongs to SOM Berthiot’s small production of unusually fast Flor normal lenses.

Production Evolution

Other 50mm f/1.5 Flor lenses exist in different camera mounts and in later professional conversions. This profile is restricted to the coupled Leica thread version documented as such.

Special Editions/Variants

Minor engraving and mechanical differences may exist among surviving examples. No reliable evidence supports splitting them into separate optical profiles.

Collector Notes

Original LTM construction, rangefinder coupling and the heavy chrome barrel are central identification points. Coating condition and internal corrosion deserve close inspection on surviving lenses.