Canon Serenar 50mm f/1.9

Canon Serenar 50mm f/1.9

This six-element normal lens marks a starting point for Canon as an optical maker, standing among the company's earliest fast rangefinder lenses sold under the Serenar brand. It was designed in the immediate postwar years and, like much of the early Japanese rangefinder output, drew openly on Leitz practice; collectors and reviewers consistently treat it as a Japanese answer to the Leitz Summar and Summitar [2][3][4]. Canon Camera Museum records list the lens as marketed in January 1949 at an original price of 29,500 yen, while collector references attribute the optical design to Kuroki Masana and date the f/1.9 design to April 1949 [1].

Optically the lens is a double-Gauss arrangement of six elements in four groups, a layout close to the Summar rather than the seven-element Summitar. It uses a collapsible barrel with an infinity lock, echoing the contemporary Leica 50mm lenses, and carries a coated front group, which gives it a practical edge over the uncoated early Leitz optics it imitated. The aperture is clickless and the scale runs from f/1.9 to f/11 with a little travel beyond the f/11 mark, and the iris forms a rounded opening rather than the hexagonal shape of some rivals. The lens mounts in Leica thread mount (M39/LTM), is rangefinder coupled, focuses to about a meter, and fits Leica, Canon, and other thread-mount bodies directly or through standard adapters. The barrel is finished in chrome/silver and the lens is comparatively dense for its size at the recorded 230 grams.

For identification, the lens is engraved Serenar and is marked in feet on the early examples; collector listings of the Canon screw-mount range place it within a family that progressed from the slower f/3.5 and f/4 Serenar lenses to this f/1.9, after which Canon moved to a rigid, brass f/1.8 design in November 1951 that initially kept the Serenar name before the line shifted to the Canon brand. Buyers should be aware that several Serenar focal lengths and speeds were sold close together, so the f/1.9 should not be confused with the later 50mm f/1.8.

Optical qualities

Rendering Documented impressions describe a lens with pronounced vintage character rather than clinical correction. Users report some field curvature, corners that stay soft at the wider apportures, and out-of-focus areas that can become busy or swirly when shot wide open, with a soft glow that suits atmospheric and low-light work; stopped down, the lens is reported to become sharp across the frame. Reviewers also note swirly background rendering at full aperture in their own samples.

Flare resistance At least one user reports little tendency to flare except when the lens is aimed directly at a strong light source, and recommends a hood for both contrast and protection.

History

Development and Launch The Serenar 50mm f/1.9 belongs to Canon's formative period as a lens manufacturer, when the firm (and its predecessor Seiki Kogaku) built 39mm screw lenses under the Serenar name primarily for its own rangefinder bodies, though they fit Leica and other thread-mount cameras as well. The lens is widely cited as Canon's first lens series produced as its own optic, and is frequently used to illustrate how the Japanese camera industry began with Leica-derived designs. Canon Camera Museum dates its marketing to January 1949, and collector records credit the design to Kuroki Masana with an April 1949 design date, describing it as collapsible with an infinity lock and marked in feet.

Production Evolution Within the Serenar standard-lens range, the f/1.9 sat above the slower prewar and early postwar 50mm Serenar lenses and was succeeded by a faster f/1.8 design in November 1951; that successor used a rigid brass barrel with an infinity lock and was likewise first sold as a Serenar before later examples carried the Canon name. The f/1.9 itself retained its collapsible Leica-style construction and coated glass throughout its run.

Collector Notes The lens is valued as an early, affordable example of postwar Japanese optics with strong character wide open. Compared with the Leitz lenses it imitated, its coated and reportedly harder front glass tends to survive better than uncoated Summar and early Summitar elements, though as with any lens of this age, haze, cleaning marks, and coating wear are worth checking before purchase. Because Canon offered several closely spaced 50mm Serenar variants, verify the f/1.9 marking and the collapsible barrel rather than relying on the Serenar name alone. Note also a minor discrepancy in the recorded filter size: the Canon Camera Museum specification page lists a 40mm filter diameter for this lens, where LeicaLensList records 41mm.