Olympus Zuiko C 4cm f/2.8

Olympus Zuiko C 4cm f/2.8

The chief distinction of the Olympus Zuiko C 4cm f/2.8 is that it is the only lens Olympus ever produced in Leica screw mount, which alone secures its place in collections of M39 optics from outside the German makers [1][2]. Olympus advertised it as a wide-angle in the May 1950 issue of the Japanese magazine Asahi Camera, promoting the 40mm angle of view as a fresh perspective for colour photography. During the same period Olympus also offered a separate Zuiko 4cm f/3.5 in Exakta mount, but the f/2.8 screw-mount version remained its sole excursion into the Leica thread-mount system.

Optically the lens uses a five-element design arranged in four groups, with three single elements at the front and a cemented doublet at the rear, a layout reported to be shared with the Super-Zuiko 4.0cm f/2.8 made for the short-lived Olympus 35 II camera. The barrel is a rigid, all-chrome unit with a focusing tab and an infinity stop, and it takes roughly half a turn to run the focus down to its closest setting of about a metre. The aperture is set on a scale graduated to f/16. As an LTM lens it threads onto Leica screw bodies and, by adapter, onto M-mount cameras, though the barrel itself is not rangefinder-coupled, so focusing relies on the scale rather than the camera's rangefinder.

For identification, the rear of the mount typically carries a two or three digit number engraved by hand for factory purposes rather than as a sequential serial number. Some examples are marked with a red "C," the designation noted in collector listings, indicating the coated optics of the period. Because production was limited and the lens never reached the volumes of Olympus's later camera-mounted optics, surviving examples are uncommon and command collector interest as curiosities of early postwar Japanese lens making.

Optical qualities

Rendering Documented performance data for this lens is limited. It is a coated five-element wide-angle of early-1950s design, so its rendering should be read in that context rather than against modern multicoated optics. Reliable independent test data on sharpness, contrast, bokeh, flare, distortion and vignetting is scarce, and no consistent body of review evidence is available to characterise its behaviour in detail. Collectors generally value it for its rarity and historical interest rather than for any documented optical advantage.

History

Development and Launch Olympus brought the Zuiko 4cm f/2.8 to market around 1950, when it was advertised in Asahi Camera as a wide-angle option for the growing Leica screw-mount user base in Japan. The marketing emphasised the angle of view in combination with colour film, reflecting the commercial interest in colour photography at the time. The lens shares its optical formula with the Super-Zuiko 4.0cm f/2.8 fitted to the Olympus 35 II, tying its development to Olympus's own rangefinder camera program.

Special editions No major factory special variants, military versions or alternate finishes for this lens are widely documented; it is generally encountered as a single chrome screw-mount type, sometimes bearing a red "C" coating mark.

Collector Notes Buyers should expect the hand-engraved two or three digit number on the rear of the mount, which is a factory marking and not a conventional serial number, so it cannot be used to date examples precisely. As with most lenses of this age, the coatings and glass should be checked for haze, cleaning marks and separation in the cemented rear doublet before purchase. The small filter thread is unusual, so any filters or accessories should be confirmed to fit. Given the lens's rarity, originality of the chrome barrel, focusing tab and engravings is worth verifying.