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

RE GN Topcor M 50mm f/1.4

Topcon · Exakta · 1973 · Modified Gauss type, seven elements (Paillard catalogue)

our own finding

Also known as: RE GN Topcor M 50mm f/1.4 · RE GN Topcor M 50mm f1.4 · RE GN Topcor M 50mm F1.4 · RE GN Topcor M 50mm 1:1.4 · RE GN Topcor M 1:1.4 f=50mm · RE GN Topcor M 1:1.4 50mm · RE GN Topcor M 1.4/50 · RE GN Topcor M 50/1.4 · RE GN Topcor 50mm f/1.4 · RE GN Topcor 50mm f1.4 · RE GN Topcor 1:1.4 f=50mm · RE GN Topcor F1.4 · RE.GN Topcor M 50mm f1.4 · REGN Topcor M 50mm f1.4 · REGN Topcor 50mm f1.4 · REGN Topcor M 1:1.4 f=50mm · REGN Topcor M 1:1.4 · GN Topcor M 50mm f/1.4 · GN Topcor M 50mm f1.4 · GN Topcor M 1:1.4 f=50mm · GN Topcor M 1.4/50 · GN Topcor M 50/1.4 · Topcor M 1.4/50 · Topcor M 1:1.4 f=50mm · GN Topcor 50mm f1.4 · GN Topcor 50mm f/1.4 · Topcor M 50mm f1.4 · Topcor M 50mm f/1.4 · Topcon 50mm f1.4 RE GN · Topcon 50mm f/1.4 RE GN · Topcon RE GN 50mm f1.4 · Topcon GN Topcor 50mm f1.4 · Topcon GN 50mm f1.4 · Tokyo Kogaku RE GN Topcor M 50mm f1.4 · REGNトプコールM 50mm F1.4 · REGNトプコール 50mm F1.4 · RE GN トプコール M 50mm F1.4 · RE GN トプコール M 50/1.4 · GNトプコールM 50mm F1.4 · GNトプコール 50mm F1.4 · トプコール GN 50mm F1.4 · トプコン RE GN トプコール M 50mm F1.4

Variants & identification

Variant Mount Years Serial ranges Production
RE GN Topcor M 50mm f/1.4 (black) Topcon RE (Exakta-type bayonet) 1973 — —
  1. Specifications. The Maxifiche gives 7 elements, 47°, f/1.4–16, 0.4 m closest focus, bayonet hood, 62 mm filter and 340 g. Paillard's catalogue gives 7 elements, 45°, 62 mm, 1.3 ft and 13 oz (350 g), and calls it a modified Gauss type. Modern Photography gives stops to f/16 in both its reports, but focusing to 16 in. (about 0.41 m) in March 1974 and to 15 in. (about 0.38 m) in December 1975; both its reports describe the lens as 1¾ in. deep and 2⅝ in. in diameter. Tokyo Kogaku's RE300/RE200 instruction book gives 7 elements, 47°, f/1.4–16, 0.4 m (16 in), 62 mm and 340 g. The weight set is the 340 g of the instruction book and the Maxifiche, against Paillard's 13 oz (350 g); no group or blade count is published in the sources consulted.
  2. Focal length. Modern Photography measured an actual focal length of 51.8 mm in March 1974.
  3. Super DM standard lens. The Maxifiche's model table gives the Super DM's standard lens as RE GN Topcor 1.4 or 1.8/50mm, but its own Super DM page reads 'f/1.4 ou 1.8 de 58mm'. Paillard, Modern Photography (1974 and 1975) and Topcon Club all say 50mm.
  4. Bodies. The lens has the RE mount, which Topcon Club describes as the Exakta mount with mechanisms added from the RE Super on, and Paillard says every RE Topcor has 'a Topcon (Exakta) bayonet mount'. On the Super DM, RE Super and Super D it couples to the open-aperture TTL meter; the Super DM's CC finder also shows the set aperture in the viewfinder (Paillard; Maxifiche; Modern Photography). The Maxifiche says the RE-2 keeps the RE Super's TTL cell and that every RE lens meters at full aperture; Topcon Club says the RE-2 couples its meter through a sliding resistor rather than the RE Super's chain. The RE200 and RE300 of 1977–78 use the same RE mount and meter at full aperture (Topcon Club), and their instruction book lists the RE GN Topcor M 50mm f/1.4 with automatic diaphragm and full-aperture metering. The RS has the RE Super's body shape but no TTL meter, only an external clip-on meter coupled to the shutter (Topcon Club); Topcon Club finds many RS bodies with RE Auto-Topcors, but no source describes the GN lenses on an RS, and the lens could not meter on it in any case. The R, RII and RIII have no TTL meter either. The Maxifiche says the R's bayonet has no coupling at all and Topcon Club that the R body has no automatic-diaphragm mechanism, everything being in its own Auto-Topcors; the RII added a lever in the bayonet (Maxifiche). No source consulted describes how an RE lens's automatic diaphragm behaves on the R, RII or RIII; on an R nothing in the body would work it. Those bodies stay linked because no source shows the lens failing to fit them. The Maxifiche's warning runs the other way: it is the F Auto-Topcors of 1960–62 that must not be used on RE bodies.
  5. Exakta and IC-1. The Maxifiche says the Topcon bayonet is a fully compatible Exakta bayonet and that Exakta lenses need no adapter on Topcon bodies, with exceptions: some automatic Exakta lenses, notably Carl Zeiss Jena's of 1961–70, foul the outer ring of the Topcon bayonet. No source consulted documents this lens on an Ihagee Exakta body. The leaf-shutter IC-1 has a different (UV) mount; Paillard sells an adapter (#83530) for putting UV Topcors on the Super DM, not the other way round.
  6. Prices. Paillard's catalogue price is $234.45 for the lens with hood. Its outfits with this lens are the Supreme I (#80000, Super DM with CC finder, lens, hood and auto winder) at $727.45 and the Super DM with CC finder, lens and hood (#80010) at $603.95. The catalogue is undated; its $727.45 is the price Modern Photography gives for the outfit in March 1974. In France the Maxifiche reports a Super DM with the GN 1.4/50 at 3,408 Fr in June 1974, against 2,920 Fr with the GN 1.8/50 and 4,000 Fr for a Nikon F2 with a 1.4/50mm. These are retail prices of the time, not auction results. No Japanese list price has been found.
  7. Dates. The Maxifiche gives both RE GN lenses as the standard lenses of the Super DM, which it dates 1973–1976; Topcon Club gives 1973 for the Super DM's launch. No end date for the lens is published. Topcon Club says Tokyo Kogaku ended production of its 35mm cameras in 1980 and their sale in Japan in 1981.
How to tell them apart (expand)
  • RE GN TOPCOR M 1:1.4 f=50mm on the front ring. The M marks this lens: the f/1.8 GN lens reads RE GN TOPCOR 1:1.8 f=50mm. The RE Auto-Topcor f/1.4 standard lens of the RE Super and Super D is a 58mm
  • A guide-number scale beside a GN mark on the focusing ring, and a black tab at the rear of the barrel that locks in the guide number
  • Focuses by a slotted spiral cam and peg rather than a helicoid (Modern Photography)
  • Not the leaf-shutter-system UV Topcor or Hi-Topcor lenses of the Wink Mirror, Unirex and IC-1, which have a different mount, and not Nikon's GN Nikkor 45mm f/2.8

RE GN Topcor M 50mm f/1.4 (black):

  • Front ring engraved RE GN TOPCOR M 1:1.4 f=50mm, TOKYO KOGAKU and LENS MADE IN JAPAN (Paillard catalogue photograph, p.4)
  • Aperture ring 1.4 2 2.8 4 5.6 8 11 16; stops only to f/16, where the f/1.8 GN lens goes to f/22
  • Guide numbers 32 to 250 in orange on black on the focusing ring, a GN mark, and a textured black tab at the rear of the barrel that slides forward to couple aperture to focus (Modern Photography, March 1974)
  • Black barrel only: the Maxifiche says the RE GN lenses are always black
  • 62 mm filter thread and bayonet hood; Paillard lists one hood (#82000) for both GN lenses

Serial-range notes

No lens serial published
Modern Photography's March 1974 test heads its resolution and contrast tables '50mm f/1.4 Topcon No. 7205171', but the same report gives 7205171 as the camera's body number, which fits the Super DM's 72 prefix. It is not a lens serial. No lens serial number is quoted in any source consulted.

Specifications

Formula
Modified Gauss type, seven elements (Paillard catalogue)
Construction
7 elements
Aperture range
f/1.4–f/16
Min. focus
0.4 m
Weight
340 g
Filter
62 mm
Years manufactured
1973
Country
Japan
Coating
Multi-coated on every group (Paillard; Topcon Club)
Original price
$234.45 with hood (Paillard Inc. US catalogue list price, c.1974) (today $1,490)

What reviewers say

History

The RE GN Topcor M 50mm f/1.4 was the standard lens of the Topcon Super DM of 1973, which Topcon Club calls the last camera of Tokyo Kogaku’s RE Super line. It and the cheaper RE GN Topcor 50mm f/1.8 took the place of the 58mm RE Auto-Topcors that had been the standard lenses of the RE Super and Super D (Maxifiche), though Paillard still listed the RE Auto-Topcor 58mm f/1.4 beside them at $200.00. Only the f/1.4 carries the M, and only it is described as multi-coated: Paillard’s US catalogue calls it multi-coated and says nothing of coating for the f/1.8, and Topcon Club says the f/1.4 was multi-coated on every group. Paillard lists it at $234.45 with hood. Its Supreme I outfit (Super DM, CC finder, this lens, hood and auto winder) cost $727.45, and a Super DM with CC finder, lens and hood $603.95. The catalogue is undated, but Modern Photography quoted the same $727.45 in March 1974. In France the Maxifiche of the Club Niépce Lumière reports a Super DM with the GN 1.4/50 at 3,408 francs in June 1974, against 2,920 francs with the f/1.8 and 4,000 for a Nikon F2 with its 50mm f/1.4. All of these are retail prices of the day. No Japanese list price has been found.

GN stands for guide number, and Topcon called the system Flash Matic. With the flash’s guide number set on the lens, the aperture follows the focusing distance, so a manual flash exposes correctly wherever the subject is. Modern Photography describes how to set it up: focus at infinity, open the lens to f/1.4, turn the focusing ring until the guide number for the flash and film (engraved in orange on black, from 32 to 250) sits against the red dot on a black tab at the rear of the barrel, then slide the tab forward to engage the ring. The magazine found it worked well as long as the photographer focused on the part of the scene that needed correct exposure. It also notes that the lens will not focus beyond the flash’s range, a built-in warning. Nikon’s GN Nikkor 45mm f/2.8 came first. According to Topcon Club, Topcon’s version differs because it has a specially shaped cam in the focusing ring, so that focus and aperture turn in equal steps. Nikon avoided the cam by keeping its lens slow and short. Topcon Club adds that the aperture clicks release once the guide number is coupled, so intermediate apertures are set freely. It also reports that Nikon later traded the use of its GN-lens patent for the use of Topcon’s open-aperture metering patent when it moved to Ai. Modern Photography singled out the focusing mount: instead of a helicoid, a slotted spiral cam in the barrel takes a peg on the inside of the focusing ring. Paillard calls it “exaggerated cam action focusing”. Away from flash, it works like any RE lens, with a fully automatic diaphragm and metering at full aperture.

Paillard calls the lens a modified Gauss type of seven elements, and the Maxifiche also gives seven. The Maxifiche gives 47°, f/1.4 to f/16, 0.4 m closest focus, a 62 mm filter and 340 g. Paillard gives 45°, 1.3 ft and 350 g, and Modern Photography gives focusing to 16 inches in its March 1974 report and 15 inches in December 1975. Modern Photography measured the actual focal length at 51.8 mm. In its March 1974 test it rated resolution above average for an f/1.4: 59 lines/mm in the centre wide open, rising to 84 from f/4 to f/8. Flare from spherical aberration was fairly large at f/1.4 and virtually gone by f/4, and from f/5.6 the lens was “particularly crisp and sharp”. The report’s tables carry the number 7205171, but the text gives this as the camera’s body number, so no lens serial is on record. The Maxifiche says the RE GN lenses were made only in black. No other version is recorded: no chrome lens, no Beseler, Hanimex or Exakta-badged copy, and no U.S. NAVY marking. Topcon Club reports that an RE GN Topcor 35mm f/1.8 was announced in the mid-1970s and came close to sale, but was dropped.

The lens has Topcon’s RE bayonet, which Topcon Club describes as the Exakta mount with various mechanisms added from the RE Super on. It meters at full aperture on the RE Super, Super D, Super DM and RE-2, and on the RE200 and RE300 of 1977–78, which keep the mount. The Super DM’s CC finder also shows the set aperture in the viewfinder. The RS has no TTL meter, and no source describes the GN lenses on one. The earlier R, RII and RIII have no meter to couple to. The R also has no diaphragm mechanism in the body, and no source describes how an RE lens’s automatic diaphragm behaves on those three bodies. The lens does not fit the IC-1 or the other leaf-shutter Topcons, whose UV mount is different. Paillard sold an adapter to put their UV Topcors on the Super DM, not the reverse. The Maxifiche says Exakta lenses fit Topcon bodies, but no source consulted documents this lens on an Ihagee Exakta.

When buying, check that the front ring reads RE GN TOPCOR M 1:1.4 f=50mm. The f/1.8 GN lens has no M and stops down to f/22. The RE Auto-Topcor f/1.4 of the RE Super years is a 58mm. Japanese listings seen title it with the engraving, RE GN TOPCOR M 50mm F1.4, sometimes adding トプコール and 東京光学. Check that the diaphragm closes and reopens cleanly. Slide the GN tab forward and make sure it couples to the focusing ring, and that the aperture then moves smoothly with the focus. The focusing mount is a cam and peg rather than a helicoid, so feel for roughness or play. Paillard sold the lens with its bayonet hood and also listed the hood on its own as #82000, the same part as for the f/1.8.

Expand Collapse

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

These photographers keep all rights to their work — enjoy it at the source.

Sample photo wanted — shot with a RE GN Topcor M 50mm f/1.4? We'd love to feature it (with credit).

Live listings

Asking price, USD: a median of $400 across 5 fixed-price listings on 2026-11-10 (middle half $340–$600). First day tracked.

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

Buying from Yahoo! Auctions outside Japan. It is a domestic marketplace: sellers ship within Japan, and most will not register an overseas buyer. A proxy service bids on your behalf, receives the item and forwards it, for a fee and a wait. Buyee, Jauce and ZenMarket each accept a Yahoo auction number directly. Listed alphabetically for information — none is recommended over another, and none of these is an affiliate link.

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

Sources (11)

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.