Tanaka Kogaku Tanar 50mm f/3.5

Tanaka Kogaku Tanar 50mm f/3.5

The Tanar 50mm f/3.5 was the entry-level standard lens that introduced Tanaka Kogaku's screw-mount system, appearing as the first lens offered for the Tanack 35, the company's early Japanese Leica copy. [1][2] Built on a classic Tessar-type optical layout of four elements in three groups, it represented the modest, affordable end of the Tanar standard line, where the faster f/2.8, f/2 and f/1.5 lenses drew most buyers. [2] Tanaka Kogaku was a small Tokyo-area maker that began work on a Leica copy in 1952 and built its Tanar lenses in Leica screw mount to equip a succession of Tanack bodies through the mid and late 1950s. [1]

Optically the lens uses the Tessar formula, and the maker's own testing reported a resolution of about 80 lines per millimeter at the center and 40 at the corners at an unspecified aperture. [2] It carries a nine-blade diaphragm and focuses to a little over a meter in its later close-focusing form. The aperture ring sits on the front of the barrel and is graduated from f/3.5 to f/22, while focus is set by a tab with an infinity lock. [2] Like the other Tanar lenses, it uses a straight helical so that the front of the barrel does not rotate during focusing. [2] The mount is the standard 39mm Leica screw thread (LTM), which makes the lens physically compatible with Leica screw bodies and, through adapters, with later M-mount and mirrorless cameras; the early examples were graduated only in feet. [2]

Several distinct versions are documented. The earliest is an all-chrome collapsible barrel, the first lens sold for the Tanack 35 and seen in documents of mid to late 1953, with the front rim engraved Tanaka Kogaku TANAR 1:3.5 F=50mm. [2] A rigid-barrel version followed and was available by March 1954, sharing a 3.5-foot minimum distance and a single row of milling on its rings. [2] A close-focusing version arrived after the Tanack IV-S in early 1955, reaching 1.5 feet, with the closest distances uncoupled from the rangefinder and marked in red, a slightly taller base, a dual row of milling, and a reversed aperture ring. [2] The final form is the chrome Tanar H.C. 5cm f/3.5, an update of the close-focusing lens with a black front bezel reading Tanaka Kogaku Japan TANAR H.C. 1:3.5 F=5cm, the H.C. denoting hard coating, dated from about November 1955. [2]

Optical qualities

Rendering Independent published testing of this lens is scarce, so its character is best described from its design and the maker's own figures rather than modern reviews. As a coated Tessar-type four-element design, it follows a long-established formula known for good central definition at moderate apertures, consistent with the manufacturer's measured resolution of roughly 80 lines per millimeter at the center falling to 40 at the corners. [2] With a modest f/3.5 maximum aperture, it is a slow standard lens rather than a fast portrait optic, and detailed claims about its bokeh, flare behavior or digital performance are not supported by reliable documentation.

History

Development and Launch Tanaka Kogaku began developing a Leica copy, the Tanack 35, in 1952 and released it in 1953, designing it with help from a former employee tied to the lineage behind Nicca and the earlier Nippon Leica copy. [1] The collapsible Tanar 50mm f/3.5 was the standard lens that launched alongside this first body, placing it at the very start of the Tanar line. [2] The company sold its standard lenses mostly as a set on a Tanack body, and the f/3.5 served as the least expensive option in that lineup. [2]

Production Evolution The lens passed through a clear sequence of barrel changes that track the development of the Tanack cameras: the chrome collapsible original of 1953, a rigid barrel available by March 1954, a close-focusing version introduced after the Tanack IV-S in early 1955, and finally the hard-coated H.C. version from about late 1955. [2] Confirmed serial numbers run in a 29xxx range for the collapsible and early rigid lenses, from 29080 up to 30197, with later close-focusing and H.C. examples recorded in a 31xxx range such as 31006 and 31484. [2] The f/3.5 sold separately for about 6,000 yen in the mid-1950s, but it was the slowest seller of the standard lenses, since the f/2.8 carried only a small premium, and it was apparently withdrawn from the catalogue not long after being advertised in mid-1958. [2]

Special editions No widely documented military, export-only or unusual factory finishes are recorded specifically for the f/3.5. The H.C. version appears to have been made only in chrome, and there is no evidence it was produced in the black finish later adopted on other Tanar lenses. [2]

Collector Notes This is a scarce lens from a small maker that never organized large-scale export, so surviving examples are uncommon and most often found mounted on a Tanack body rather than sold separately. [1][2] Identification rests on the engraving and barrel type: collapsible versus rigid, the single versus dual row of milling, feet-only scales, the red close-focus markings on later examples, and the black H.C. bezel with H.C. in red on the hard-coated version. [2] The maker described the f/3.5 itself as having a relatively poor overall finish on the earliest collapsible barrels, so condition varies. [2] As with any lens of this age, prospective buyers should check the coatings and glass for haze and confirm that the engraving and barrel features are consistent with a documented variant.

Sources

• [1] Camerapedia. Tanaka. https://camerapedia.fandom.com/wiki/Tanaka
• [2] Camerapedia. Tanar lenses. https://camerapedia.fandom.com/wiki/Tanar_lenses