Bronica GS-1
Zenza Bronica · Bronica GS mount · 55.6 × 69.0mm on 120 or 220 film with the GS 6×7 back (Tamron Japan); 6×6 and 6×4.5 backs, and a Polaroid pack-film back, were also made (camera-wiki) · 1983
via machine translation — corrections welcomeAlso known as: Bronica GS-1 · Zenza Bronica GS-1 · Bronica GS1 · Zenza Bronica GS1 · Bronica GS-1 6x7 · Bronica GS-1 body · ZENZA BRONICA GS-1 · ゼンザブロニカ GS-1 · ブロニカ GS-1 · ブロニカ GS1 · ゼンザブロニカ GS1
Variants & identification
| Variant | Mount | Years | Serial ranges | Production |
|---|---|---|---|---|
| GS-1, first series (serials 310xxxx, 1983) | Bronica GS | 1983 | 310xxxx — about 1,500 bodies (camera-wiki) | About 1,500 (camera-wiki) |
| GS-1, revised series (serials 311xxxx–313xxxx) | Bronica GS | 1983–2002 | 311xxxx–313xxxx — about 21,000 bodies (camera-wiki) 3118000 — the one body recorded with brown leather (camera-wiki) | About 21,000, of which the last ~12,000 carry the black-button finish; about 22,500 GS-1 bodies in all (camera-wiki) |
- Release month: Tamron's Japanese product list and Japanese Wikipedia give April 1983; camera-wiki gives March 1983. Both agree on the end, June 2002, which Tamron's page states as 平成14年6月.
- Body dimensions and the 1,830g are Tamron Japan's figures for the standard set; camera-wiki gives no absolute dimensions and only the 630g body weight. Chemical Cameras quotes 106.5 × 116 × 196.5mm, against Tamron's 117.7mm height, and sets it beside 104 × 144 × 233mm and 2.69kg for the Mamiya RB67.
- The ¥276,000 and ¥357,000 are 参考価格, reference prices, as Tamron's page of 2001 labels them, not launch prices; no 1983 list price was found. The dollar figures are body-only list prices from Tamron USA's 1996 price list and 2004 product page.
- Power: one 6V 4LR44 alkaline or 4SR44 silver-oxide cell (Tamron Japan; Japanese Wikipedia citing クラシックカメラ専科 No.57). Ross Jukes calls it a PX28, the same size. Commenters on Chemical Cameras recommend the silver-oxide cell and report a flickering speed LED cured by changing to a 4SR44; the kakaku.com reviewer warns of weak batteries in the cold.
- Shutter choice: camera-wiki reports that a #1 shutter with a 30mm opening was considered and rejected, because the helicoids would have grown to 100mm or more and the top speed would have fallen to 1/400; the #0 kept 1/500.
- TTL flash: dedicated to the Speedlight G-1 through the Speed Grip G and AE prism. camera-wiki warns that the Minolta-dedicated Sunpak MX-2D and Metz SCA 386 modules do not give TTL on the GS-1 despite some sources claiming they do, and suggests the G-1 shares parts with, and may have been made by, National/Panasonic.
How to tell them apart
- Bronica GS four-claw bayonet, a mount shared with no other Bronica body: the flange distance is the same 85mm as the SQ but the mounts do not interchange (camera-wiki)
- Shutter-speed dial on the body, 16s to 1/500 plus T and B, with the speed shown by a lit display on half-pressure of the release that doubles as the battery check (Tamron Japan)
- 6×7 back fixed in landscape; there is no revolving back on any GS-1 (camera-wiki)
- Seven-digit serial beginning 310–313; black rather than silver buttons on the last ~12,000 bodies (camera-wiki)
- Die-cast light-alloy body, back and stainless-steel mount with reinforced-plastic front and side covers (camera-wiki)
GS-1, revised series (serials 311xxxx–313xxxx):
- The last 12,000 or so bodies have small finish changes, among them black buttons in place of the earlier ones (camera-wiki)
- GS-1, first series (serials 310xxxx, 1983): The launch series. camera-wiki separates it from the later bodies only by serial block and size; no external difference is described, and the end year of the block is not given.
- GS-1, revised series (serials 311xxxx–313xxxx): camera-wiki's 'revised series', which makes up the bulk of production. It does not say what was revised beyond the finish changes on the last 12,000, and it dates none of the blocks. One body, serial 3118000, has been seen with brown leather instead of the standard covering; camera-wiki records it without saying whether it left the factory that way.
Serial-range notes
- 310xxxx–313xxxx
- Seven digits beginning 310 to 313, by camera-wiki's account: 310xxxx for the first ~1,500 bodies and 311xxxx to 313xxxx for the ~21,000 that followed, the last ~12,000 of them with black buttons. No year table has been published; the blocks date a body only relative to one another across a nineteen-year run.
Specifications
- Format
- 55.6 × 69.0mm on 120 or 220 film with the GS 6×7 back (Tamron Japan); 6×6 and 6×4.5 backs, and a Polaroid pack-film back, were also made (camera-wiki)
- Finder (waist-level finder G (standard))
- folding hood with magnifier, 4.3× (camera-wiki) · 4.3× magnification · 94% coverage
- Finder (prism finder G)
- eye-level pentaprism, unmetered, derived from the ETR prism (camera-wiki) · 0.87× magnification · 94% coverage
- Finder (AE prism finder G)
- metered pentaprism giving aperture-priority automation, EV 2–17 at ISO 100 (camera-wiki) · 0.87× magnification · 94% coverage
- Finder (rotary AE prism finder G)
- 90° rotating metered prism with average and spot metering (camera-wiki) · 94% coverage
- Shutter
- Seiko #0 electronically controlled leaf shutter in each Zenzanon-PG lens, timed by the body; mechanical fallback of about 1/500 without battery (Tamron Japan) · 16s–1/500, T and B (Tamron Japan); 1/8-stop steps under the AE prism (camera-wiki) · flash sync X contact only, at every shutter speed; TTL-OTF flash through the AE prism finder G, Speed Grip G and Speedlight G-1 (Tamron Japan; camera-wiki)
- Film advance
- Single-turn crank; the crank can also be worked in small increments (Tamron Japan). Mirror lock-up by a lever at the lower left of the front, multiple exposure by a lever on the right below the crank (Japanese Wikipedia)
- Back
- Detachable, interchangeable film backs for 120, 220 and Polaroid pack film (Tamron Japan): 6×4.5, 6×6 and 6×7 roll-film backs in 120 and 220 versions, with the 6×7 back fixed in landscape and no revolving back, a size-and-weight choice camera-wiki ascribes to the design. 35mm backs in 24×36 and 24×69 were announced but never made (camera-wiki).
- Meter
- None in the body. The AE prism finder G meters EV 2–17 at ISO 100 for aperture-priority automation; the rotary AE prism finder G adds spot metering (camera-wiki). Film-speed and exposure-compensation dials are provided (Tamron Japan).
- Motor drive
- Not compatible — The Speed Grip G is a manual winding grip with a hot shoe for the Speedlight G-1, not a motor (camera-wiki)
- Weight
- 630 g
- Dimensions
- 106.5 × 117.7 × 196.5 (W × H × D) and 1,830g with the Zenzanon-PG 100mm f/3.5, 120 back and waist-level finder (Tamron Japan); body alone 630g (camera-wiki) mm
- Country
- Japan
- Original price
- Japan, reference prices on Tamron's page of c.2001: ¥276,000 for the standard set (body, GS120 6×7 back, Zenzanon-PG 100mm f/3.5, waist-level finder G) and ¥357,000 for the AE set (the same with AE prism finder G and Speed Grip G). United States, body only: $2,047 on Tamron's April 1996 list and $2,319 on its 2004 page. (today $4,090)
- Accessories
- Finders: waist-level finder G, prism finder G, AE prism finder G, rotary AE prism finder G; all 94% coverage (camera-wiki) · Film backs: GS120 and GS220 in 6×7, 6×6 and 6×4.5; Polaroid pack-film back (Tamron Japan; camera-wiki) · Speed Grip G, a manual winding grip with hot shoe, and the dedicated Speedlight G-1 for TTL-OTF flash (camera-wiki) · Revolving tripod adapter G, used with the rotary finder for vertical framing (Japanese Wikipedia) · Teleconverters G 1.4X (29 × 89mm, 420g) and G 2X (64.4 × 89mm, 680g), shown with the 110mm and 200mm at Photokina 1984 (Tamron Japan; camera-wiki) · Auto extension tubes G-18 and G-36; the 36mm tube takes the Macro 110mm to 1:1 (camera-wiki) · Fotodiox adapters put Mamiya 645, Pentax 645, Nikon F, Canon EF, Pentax K and Sony Alpha lenses on the body (camera-wiki)
Supplied in the standard set (Tamron Japan). camera-wiki gives 94% field coverage for every GS-1 finder. Japanese Wikipedia and Chemical Cameras both note that with the 6×7 back fixed in landscape, vertical framing from the hood means turning the whole camera; the rotary finder G with the revolving tripod adapter G is the maker's answer.
0.87× with the 100mm lens at infinity, −1.5 dioptre eyepiece, 425g (camera-wiki)
460g (camera-wiki). In aperture priority the camera sets the shutter in 1/8-stop steps while the display rounds to half stops; the manual dial on the body works in full stops. Supplied in the AE set with the Speed Grip G (Tamron Japan). TTL-OTF flash metering with the Speedlight G-1 works through this finder (camera-wiki).
Turns the eyepiece for vertical framing without moving the lens axis, which Japanese Wikipedia (citing カメラ年鑑'98 p.273) pairs with the revolving tripod adapter G; camera-wiki says it is covered by patent no. 950970. Chemical Cameras: it 'makes portrait orientation much easier'.
Where sources disagree
- First (month)
- April 1983 — Tamron's Japanese product list; Japanese Wikipedia; kakaku.com's product record
- March 1983 — camera-wiki
Better supported: April 1983
Two Japanese sources, one of them the maker's successor, against one English one.
- Dimensions (mm) (height)
- 117.7mm — Tamron Japan, with 100mm lens, 120 back and waist-level finder
- 116mm — Chemical Cameras, same configuration
Better supported: 117.7mm
- Accessories (80mm lens introduction)
- 1997 — camera-wiki's lens section
- 1996 — camera-wiki's body section, linking a white-covered 80mm (serial 8400001) to the launch
The same page gives both dates and does not reconcile them; the lens is absent from Tamron USA's April 1996 price list.
What reviewers say
- Laidric Stevenson, Emulsive (March 2016, updated 2021) (blog) — Seven years with the 100mm, 110mm Macro, 65mm and 50mm: big enough for the 6×7 negative yet light enough for long handheld days, a finder in which images 'drew into focus', TTL flash with sync at every speed, and a mirror 'Ka-thunk' he cannot stop firing. 'Highly Recommended', with the warning that a kit takes time to assemble; he paid under $500 at KEH for body, prism, lens and back.
- Ross Jukes, rossjukesphoto.co.uk (blog) — 'The most underrated medium format camera ever': smaller than the RB67, RZ67 or Pentax 67 but still large, with the main controls to hand and flash sync at all speeds 'a huge plus point'. The compromises are the non-rotating back, which makes portrait framing awkward on a tripod, a dependence on one PX28 cell, and the near-impossibility of repair. About £500 for a good body; lenses sometimes under £150.
- Adrian Cowderoy, adriancowderoy.com (December 2011) (blog) — Bought in 1988 and loved 'now as much I did then' after 23 years across Europe and America with the 65mm, 100mm, 150mm and 2× converter: it fits the right hand with the prism, needed no speed grip, survived a fall down a slope with a scratch, and in all that time only the crank bent, the mirror-up lever shortened and a holder on a back broke.
- revdocjim, Chemical Cameras (c.2010–11) (blog) — With the 50, 65, 100, 150 and 200mm, the AE and rotary prisms and three backs: 'a clear winner' for handheld 6×7 SLR work at 1.83kg against the RB67's 2.69kg, 'nothing flimsy', with a smoothness of function he rates above its rivals. Commenters add a 'crystal clear' waist-level view, a shutter-release failure on one body, and the cure of a flickering LED with a silver-oxide cell.
- yama645, kakaku.com user review (May 2010) (blog) — Four stars for the AE set: a solid, heavy body that is nonetheless lighter than other 6×7 cameras, very good handling, five stars for the lenses' sharpness and rendering, but a lens line smaller than its competitors' and a battery that fades in the cold. via machine translation — corrections welcome
History
Bronica’s 6×7 came last of its three leaf-shutter systems, after the 6×4.5 ETR of 1976 and the 6×6 SQ of 1980, and it was built to a brief that camera-wiki quotes from the development notes: a Seiko #0 electronic shutter under digital control, an LED speed display, a new generation of lenses, TTL flash and multi-format backs, all in a body as small and light as the format allowed. The revolving back of the Mamiya RB67 was rejected on size and weight, and so was a larger #1 shutter, which would have stretched the lens helicoids past 100mm and cut the top speed to 1/400. What went on sale in April 1983 weighed 630g as a bare body and 1,830g with the 100mm f/3.5, a 120 back and the waist-level hood, against 2.69kg for the equivalent RB67. Tamron, which had taken over Bronica, kept it in production until June 2002 and sold the AE set at ¥357,000 in its last years; about 22,500 bodies were made.
The body is a timer and a mirror box. Each Zenzanon-PG lens carries its own Seiko #0 shutter, set from the dial on the body from 16 seconds to 1/500 plus T and B, with a mechanical 1/500 if the single 6V cell dies; flash synchronises at every speed through the X contact, and with the Speedlight G-1 on the Speed Grip G and the AE prism in place the camera reads the flash off the film, the first medium-format camera to do so and the only 6×7 to do so until the Pentax 67II fifteen years later. Four finders were made, all showing 94% of the frame: the hood, a plain prism derived from the ETR’s, an AE prism giving aperture priority from EV 2 to 17, and a rotary AE prism that turns the eyepiece through 90° for vertical pictures, which, with the revolving tripod adapter, is how Bronica answered the fixed landscape back. Backs came in 6×7, 6×6 and 6×4.5 for 120 and 220, plus Polaroid; the 35mm backs that were announced were never built.
Its reviewers agree on what it is for. Laidric Stevenson, Ross Jukes and revdocjim all keep it as the 6×7 SLR to carry rather than to bolt to a studio stand, and Adrian Cowderoy’s body, bought in 1988, had after 23 years of travel suffered nothing worse than a bent crank. The complaints are the ones the design chose: a vertical frame means turning the whole camera unless the rotary prism is fitted, the electronics depend on one battery that fades in the cold, and nobody now repairs them, so, as Jukes puts it, a broken body is more easily replaced than mended. Used prices in the reviews run from under $500 for a working outfit in 2016 to about £500 for a good body, with most lenses under £150 or $300 apiece and only the late 80mm and the special-order 500mm costing real money.
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.
Live listings
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