Zunow 50mm f1.3

Zunow 50mm f1.3

The Zunow 50mm f/1.3 is one of the lesser known fast standard lenses from Zunow, a small Japanese maker remembered chiefly for the ultrafast 5cm f/1.1 of 1953, which at its introduction was the fastest lens available for any 35mm camera [1]. The f/1.3 sat just below that headline lens in the catalogue, offering a still very fast aperture in a more conventional package. Period documentation lists it among the rangefinder lenses Zunow offered for Leica thread, Contax, Canon and Nikon mounts alongside the 35mm f/1.7, 50mm f/1.1, 50mm f/1.9 and 100mm f/2 [1]. It is far rarer than the f/1.1 and appears infrequently, mostly on the Japanese market and through specialist dealers [1].

The lens uses a seven element, five group optical layout and a Leica screw mount, and like Zunow's other fast standards of the period it follows the Sonnar lineage that defined the company's design approach [2][1]. Aperture is set with eight blades, and focusing runs to a minimum distance of one metre, which was typical of fast rangefinder fifties of the era. The barrel is finished in chrome in the screw mount form sold by dealers [2]. As with many independent LTM lenses, buyers should confirm rangefinder behaviour on a given body, since coupling accuracy across different camera makers cannot be assumed for every example.

Zunow itself evolved through several names. The firm traces to Teikoku Kogaku Kenkyujo, founded around 1930, which became Teikoku Kogaku Kogyo in 1954 and then Zunow Kogaku Kogyo, or Zunow Optical Industry, in 1956 [1]. Because of this, surviving lenses and dealer listings sometimes carry the Teikoku Kogaku name alongside Zunow, which is a point of identification rather than a sign of a different lens [2]. The company's fortunes declined at the end of the decade, and after the failure of its SLR and the loss of key customers it closed in 1961 [1].

Optical qualities

Rendering

Detailed, independent testing of the 50mm f/1.3 specifically is scarce, so firm performance claims are limited. As a fast Sonnar-derived design of the 1950s, it can be expected to share the general traits of its family, namely a soft, glowing wide open look that gains definition on stopping down. Given the limited published evidence for this particular lens, more precise statements about its sharpness, bokeh or flare control are not well supported and are best verified against a specific sample.

History

Development and Launch

Zunow's reputation rested on speed. The 5cm f/1.1 of 1953 was the first ultrafast 50mm for rangefinder cameras and was not matched until Nippon Kogaku released the Nikkor 50mm f/1.1 in 1956 [1]. After establishing that lead, Zunow broadened its range with good quality but less extreme lenses, and the 50mm f/1.3 belongs to this group of fast but more practical standards [1]. A list of Zunow lenses from 1957 records the 50mm f/1.3 among the rangefinder offerings for Leica, Contax, Canon and Nikon cameras, placing its availability in the second half of the decade [1].

Collector Notes

The f/1.3 is uncommon and is encountered far less often than the f/1.1, with most examples surfacing in Japan or through dealers who specialise in vintage Japanese glass [1]. Listings may show the lens under the Zunow or Teikoku Kogaku name, reflecting the company's name changes during the 1950s, so both labels can be correct [1][2]. As with other fast Japanese rangefinder lenses of this age, prospective buyers should check the optics carefully for haze, separation and cleaning marks, and confirm focusing and mount fit on their intended camera before purchase. Published figures for early Zunow lenses occasionally vary between sources, so individual specimens are worth verifying directly.

Sources

• [1] Crafting Pixels. Vintage lens makers – Zunow (Japan). https://pixelcraft.photo.blog/2025/03/06/vintage-lens-makers-zunow-japan/
• [2] LSKamera. Zunow Teikoku Kogaku 50mm f/1.3 LTM. https://lskamera.com/zunow-teikoku-kogaku-50mm-f13-ltm