Glass Bodies a variant-level encyclopedia of vintage lenses and cameras by iwillpat

Topcor 5cm f/2.8 (Leica screw mount)

Topcon · LTM · 1958

Also known as: Topcor 5cm f/2.8 · Topcor 5cm f2.8 · Topcor 5cm 1:2.8 · Topcor 1:2.8 f=5cm · Topcor 50mm f/2.8 · Topcor 50mm f2.8 · Topcor 50mm f2.8 LTM · Topcor 5cm F2.8 L39 · Topcor 2.8/5cm · Topcor 2.8/50 · Topcon Topcor 5cm f2.8 · Topcon Topcor 50mm f2.8 · Tokyo Kogaku Topcor 5cm f2.8 · Tokyo Kogaku Topcor 50mm f2.8 · Tokyo Kogaku Topcor 1:2.8 f=5cm · Tokyo Optical Topcor 5cm f2.8 · Tokyo Optical Topcor 50mm f2.8 · Leotax Topcor 5cm f2.8 · トプコール 5cm F2.8 · トプコール 50mm F2.8 · 東京光学 トプコール 5cm F2.8 · トプコン トプコール 5cm F2.8 · Topcor 5cm F2.8 Lマウント

Variants & identification

Variant Mount Years Serial ranges Production
Topcor 5cm f/2.8 LTM 1958 — No figure published. Topcon Club says not many seem to have been made; Camera-wiki calls it extremely rare because of very low production
  1. Date. Leica Copies Japan dates the lens to 1958, the year of the Leotax T2 and K3 on which most known copies sit, and Topcon Club ties it to the T2. koiwide says Tokyo Kogaku supplied it to Leotax in 1957. The page follows 1958. Leica Copies Japan also notes that copies turn up on the earlier Leotax F and T, which Topcon Club supports for the F.
  2. End of production. No end date has been published. The lens is not in the user manual of the Leotax TV2, a 1958 model, which Leica Copies Japan reads as a sign that it was short-lived. A Leotax T2L outfit, a model released in 1959, has one with papers that name the lens and match its serial number, so the lens was still being supplied at least that late.
  3. Close focus. koiwide gives 3.5 ft, about 1 m. The 1.07 m here is that distance in metres; no metric scale has been reported.
  4. Design. Topcon Club's cross-section page describes it as a Heliar type that makes the Tessar's front group of two elements: 'ヘリアー型で、テッサ―型の前群を二枚構成にしている'; its lens page adds that the front element is a cemented pair. Camera-wiki says the design copies Voigtländer's Color Heliar of 1952. koiwide believes it was probably the only Heliar-type standard lens made in Japanese Leica mount, and names the Konishiroku Hexanon 50mm f/2.8 of the Konica I and II as a Heliar-type lens of the same era.
  5. Other Topcor 5cm f/2.8 lenses. Tokyo Kogaku's own Topcon 35-JL rangefinder has an f/2.8 lens (Camera-wiki). Topcon Club says this lens is said to have been applied to the 35-JL's standard lens, but that the design is in fact a different one. The Topcor 5cm f/2.8 fixed on the leaf-shutter Topcon PR is a Tessar type (Topcon Club, cross-sections). Neither is this lens.
  6. Not the Fujinon. Leotax T2 and K3 bodies were sold far more often with Fuji's Fujinon 5cm f/2.8, also in Leica thread. Leica Copies Japan finds six of nine K3s with likely original lenses fitted with the Fujinon and three with this Topcor. The Fujinon is a 5-element lens with a 40.5 mm filter; check the name on the front ring.
  7. Price. No price for this lens, alone or on a camera, has been found.
How to tell them apart (expand)
  • Leica 39 mm screw mount, rangefinder-coupled; Topcor and f/2.8 on the front ring; 34 mm filter
  • Not the Topcor 3.5cm f/2.8 wide-angle in the same mount, not the Fujinon 5cm f/2.8 sold on the same Leotax bodies, and not the R-Topcor, Auto-Topcor or RE Topcor lenses for Topcon reflexes

Topcor 5cm f/2.8:

  • Front ring engraved Topcor 1:2.8 f=5cm Tokyo Kogaku (koiwide's photograph)
  • Rigid, slim barrel. Topcon Club calls it clearly a size thinner than the f/2 Topcors and styled like a slightly more upmarket version of the rigid 5cm f/3.5 (the Topcor K). Camera-wiki describes the finish as black and chrome
  • Focusing lever on a rotating helicoid, about 90 degrees from infinity to 3.5 ft, which koiwide says takes some getting used to when setting the aperture; click stops f/2.8 to f/22 at even spacing (koiwide)
  • 34 mm filter thread (koiwide; Leica Copies Japan reads the hood's '34 mm A' as the filter size), where the Topcor-S 5cm f/2 and the later Topcor 5cm f/1.5 take 40.5 mm (Leica Copies Japan)
  • Its own telescoping hood, which slides forward for use and back over the lens as a cap; three ball detents in the mounting ring hold it in either position; 'Pat.Pend' on the hood, '34 mm A' on its base (koiwide; Leica Copies Japan; Topcon Club)

Specifications

Formula
Heliar type, 5 elements in 3 groups, the front element a cemented pair (Topcon Club; Leica Copies Japan)
Construction
5 elements / 3 groups
Aperture range
f/2.8–f/22
Diaphragm blades
10
Min. focus
1.07 m
Filter
34 mm
Country
Japan

What reviewers say

History

The Topcor 5cm f/2.8 is a standard lens in Leica 39 mm screw mount that Tokyo Kogaku (Tokyo Optical, later Topcon) made for the Leotax cameras of Showa Optical (by then Leotax Camera). Topcon Club says the screw-mount Topcors were all made mainly for Leotax bodies. Leica Copies Japan dates it to 1958 and Topcon Club, the Japanese collectors’ site, ties it to the Leotax T2 of that year. koiwide gives 1957. In koiwide’s account it sat between the Topcor f/2, the expensive option, and the Topcor f/3.5, the cheap one, and he suggests that this unclear position is why it got little attention and soon disappeared. It is missing from the user manual of the 1958 Leotax TV2, and no production figure or serial range has been published. Topcon Club says not many were made, and Camera-wiki calls it extremely rare.

What sets it apart is the optics. It is a Heliar type with five elements in three groups, the front element a cemented pair. Topcon Club describes it as a Tessar whose front group is made of two elements. Camera-wiki says it copies Voigtländer’s Color Heliar of 1952, and koiwide thinks it was probably the only Heliar-type standard lens made in Japanese Leica mount. The barrel is slim and rigid, with a focusing lever, a 34 mm filter thread and ten aperture blades. It came with its own telescoping hood, engraved Pat.Pend, that slides back over the lens to serve as a cap, held in either position by ball detents. koiwide notes that the barrel styling was carried over to Tokyo Kogaku’s later RE Topcor lenses for its own reflexes.

Reviewers judge it a good lens but not an outstanding one. Topcon Club’s test at f/8 found it clean and finely sharp but without punch or the three-dimensional rendering it associates with Topcor, and ranked it with the first f/2 and the early collapsible f/3.5, a little below the Topcor-S and the 5cm f/1.5. koiwide found it soft and dull near full aperture, with weak corners. Stopped down to f/8, he found it dense and even across the frame with rich, gentle gradation, and he calls it a superb lens for that use. No price has been found, either for the lens alone or on a camera.

There is only one version. Most known copies are on the Leotax T2 and K3. Leica Copies Japan has also found it on the earlier T, TV and F, and on a T2L of 1959 whose papers name the lens and match the camera and lens numbers, though the box is labelled for the Topcor-S f/2. A camera sold with the lens does not prove that the two left the factory together. When buying, read the front ring. The same Leotax bodies were sold far more often with Fuji’s Fujinon 5cm f/2.8, which takes a 40.5 mm filter. The Topcor 3.5cm f/2.8 wide-angle is a different lens, and so are the Topcor 5cm f/2.8 fixed to the leaf-shutter Topcon PR and the f/2.8 standard lens of the Topcon 35-JL rangefinder. The hood adds a good deal to a copy’s interest, so check that it is present and that its detents still hold. The lens fits any Leica-thread body and couples to its rangefinder. As with any 1950s lens, look for haze, separation and cleaning marks, and check that the helicoid turns smoothly over its full travel.

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This history is AI-written, from the sources listed at the foot of the page. Where the record is silent it says so rather than filling the gap — but no human wrote these sentences.

Example photos

More sample photos elsewhere

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Sample photo wanted — shot with a Topcor 5cm f/2.8 (Leica screw mount)? We'd love to feature it (with credit).

Live listings

Asking price, USD: a median of $400 across 3 fixed-price listings on 2026-11-10 (middle half $300–$400). First day tracked.

Asking prices from the listings scanned, not sales; junk-flagged rows and auction lots excluded; other currencies are not converted.

Listings updated 2026-11-10. Links go to the shop or marketplace that carries the item.

Sources (7)

Every page here is assembled from public sources, and the gaps are real ones. If you own this lens, know a serial number I'm missing, or can see where I have it wrong, tell me — corrections, serials and sample photos are all worth having.