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

Zenza Bronica EC

Zenza Bronica · Bronica S mount · 55.2 × 55.2 mm on 120 (12 exposures) or 220 (24 exposures); 6×4.5 with Film Back E (Tamron spec sheet; camera-wiki) · 1972

Also known as: Bronica EC · Zenza Bronica EC · Bronica EC 6x6 · Zenzabronica EC · Bronica EC body · Bronica EC Nikkor · ゼンザブロニカ EC · ゼンザブロニカEC · ブロニカ EC · ブロニカEC

Variants & identification

Variant Mount Years Serial ranges Production
EC, full-stop shutter dial (1972–c.1979) Bronica S 1972–1979 — No production figure is known to have been published
EC, half-stop dial (c.1979 on) Bronica S 1979 — No production figure is known to have been published
  1. Weight: Tamron's spec sheet gives 1,960 g; camera-wiki prints '1,980 kg', a unit slip, and a figure 20 g apart. Tamron's is used.
  2. Battery: Tamron names one 6 V silver cell, Eveready No. 544; camera-wiki writes PX28, the same 6 V silver-oxide cell under another name; Japanese Wikipedia writes 4G13, a four-cell 6 V silver pack of the same size.
  3. Mounts by focal length are from Tamron's sheet: large bayonet for 105, 300, 400, 600, 800 and 1200 mm; small bayonet for 40, 50, 75, 100, 150 and 200 mm; the 57 × 1 mm thread for extension rings. The EC takes the S2A's lenses (camera-wiki).
  4. The standard lens is not named on Tamron's sheet. camera-wiki gives the 75 mm f/2.8 Nikkor; the Nikkor-H·C 75 mm f/2.8 'DX' was offered as the premium alternative, and Zenzanon-branded normal lenses from other makers followed as Nikkor supply tightened (camera-wiki; shiura.com as cited in the research).
How to tell them apart (expand)
  • Battery chamber for a 6 V silver cell and a battery-check function; no sign of these on any S-series body (Tamron spec sheet)
  • Shutter dial running to 4 s at the slow end, with no ASA ring in its centre and no red 'A' — the EC-TL has both (camera-wiki)
  • Mirror lock-up, which the S2 and S2A lack; the mirror is in two parts, the upper half swinging up and the lower half down (Tamron spec sheet; Japanese Wikipedia)
  • Two tripod sockets, 1/4 and 3/8 inch, and an accessory shoe (Tamron spec sheet)
  • Larger body than the S2A: 139 × 170 × 117 mm against 100 × 100 × 140 (Tamron spec sheets)
  • Electrical contacts for the TTL meter finder on the body (Japanese Wikipedia)

EC, full-stop shutter dial (1972–c.1979):

  • Shutter dial clicks in full stops, B and 4 s to 1/1000 (Tamron spec sheet)
  • Release button on the sync plug (Japanese Wikipedia, which records its removal in the c.1979 revision)
  • No ASA setting in the dial centre and no red 'A' on the dial, which belong to the EC-TL (camera-wiki)

EC, half-stop dial (c.1979 on):

  • Shutter dial with half-stop click positions (Japanese Wikipedia, citing Camera-Lens Hakusho 1979)
  • No release button on the sync plug (Japanese Wikipedia)

Specifications

Format
55.2 × 55.2 mm on 120 (12 exposures) or 220 (24 exposures); 6×4.5 with Film Back E (Tamron spec sheet; camera-wiki) · 12 on 120, 24 on 220, selected on the back (Tamron spec sheet) exposures
Finder
Interchangeable waist-level hood opening and closing in one action, with interchangeable magnifier and interchangeable Fresnel focusing screen (standard type A); prism finder A, finder C, magnifying hood and the TTL exposure-meter finder for the EC were sold (Tamron spec sheet; camera-wiki)
Shutter
Electronically timed vertical-travel focal plane; the shutter needs the 6 V battery (Tamron spec sheet; camera-wiki) · B, 4 s–1/1000 in full stops; half-stop clicks from c.1979; T by the release (Tamron spec sheet; Japanese Wikipedia) · flash sync Auto-switching, self-locking socket with dust cover: X (electronic flash) at B and 4 s–1/60; FP bulbs at B, 4 s–1/15 and 1/125–1/1000; M at B and 4 s–1/15; F at B and 4 s–1/30 (Tamron spec sheet; camera-wiki gives X 1/60, M 1/15, F 1/30, FP 1/15 and 1/125–1/1000) · no self-timer
Film advance
Crank, two full turns per frame, with fine advance possible; cocks the shutter and resets the mirror (Tamron spec sheet)
Back
Interchangeable back fully coupled to the body, with multiple-exposure switch, 12/24 selector dial, separate film-advance knob, film-type indicator and a dark-slide pocket with lid; Film Back E for 6×4.5 and a Polaroid back (Tamron spec sheet; camera-wiki). Not interchangeable with S2-series backs (camera-wiki)
Meter
None in the body; the optional TTL CdS exposure-meter finder for the EC couples through contacts on the body (camera-wiki; Japanese Wikipedia)
Weight
1960 g
Dimensions
139 (W) × 170 (D) × 117 (H) (Tamron spec sheet; camera-wiki gives 139 × 117 × 170) mm
Country
Japan
Original price
¥158,000 for the standard set of body, film back, standard lens and waist-level finder (Tamron spec sheet, which notes the set price was forced by the commodity-tax display rules of the time) (today ¥496,000)
Accessories
Film backs: 6×6 120/220 back and insert, Film Back E for 6×4.5, Polaroid back (camera-wiki) · Finders: waist-level finder, TTL exposure-meter finder (EC), magnifying hood, prism model A, viewfinder model C; focusing screens A, B, C and D (camera-wiki) · Close-up: bellows and compact bellows for EC/EC-TL, reversing ring, extension-ring set on the 57 mm thread (camera-wiki; Tamron spec sheet) · L-grip, T-grip, focus lever (camera-wiki)

Finders and film backs are new to the EC and do not interchange with the S2/S2A (camera-wiki). camera-wiki lists screens A (matte centre), B (microprism), C (split image) and D (matte).

Where sources disagree

Last
  • December 1978 — English Wikipedia
  • Still in production c.1979, when the half-stop dial and other revisions appear in the 1979 Camera-Lens Hakusho, continuing beside the EC-TL — Japanese Wikipedia

The two cannot both be right; the end date is left open.

First
  • April 1972 — Tamron; English Wikipedia
  • May 1972 — Japanese Wikipedia

Better supported: April 1972

Weight (grams)
  • 1,960 g — Tamron spec sheet
  • '1,980 kg' — camera-wiki

Better supported: 1,960 g

What reviewers say

No reviews aggregated yet — this family is still in the research queue. Written one? We'd love to index it.

History

The EC of April 1972 is the focal-plane Bronica rebuilt around electronics. The shutter is still a vertical-travel focal plane, but its speeds, B and 4 s to 1/1000, are timed electronically from a 6 V silver cell (Tamron names the Eveready No. 544, which is the PX28 camera-wiki writes), and English Wikipedia credits it as the first medium-format SLR with an electronically timed focal-plane shutter, citing the Japanese and US patents. The mirror is new too: a two-part quick-return mirror whose upper half swings up and lower half down, with the mirror lock-up the S2 and S2A lack, and the body carries contacts for an optional CdS TTL meter finder that reads through the lens (Tamron; Japanese Wikipedia; camera-wiki).

The lens mount is the S2A’s, three standards on one body: Tamron’s sheet puts the 40, 50, 75, 100, 150 and 200 mm lenses on the small bayonet at the front of the removable 14 mm helicoid, the 105 mm leaf-shutter lens and the 300 to 1200 mm lenses on the large bayonet exposed when the helicoid comes off, and extension rings on the 57 × 1 mm thread. Every S2A lens fits. The backs and finders are new and do not interchange with the earlier cameras (camera-wiki); the back gained a multiple-exposure switch, a 12/24 selector and a lidded pocket for the dark slide, and the finder a one-action hood with interchangeable screens, type A matte-centre as standard. The body grew to 139 × 170 × 117 mm and 1,960 g, with two tripod sockets and an accessory shoe, and the standard set cost ¥158,000 (Tamron).

The EC was the base of the EC-TL of 1975, which added auto-exposure, but it was not withdrawn when the EC-TL appeared. English Wikipedia ends it in December 1978; Japanese Wikipedia, citing the 1979 Camera-Lens Hakusho, records a revised EC around 1979, with half-stop clicks on the dial, a shutter that fires at B without a battery at any setting, and the release button on the sync plug removed, kept in production beside the EC-TL for buyers who did not want auto-exposure. camera-wiki notes that as Nikkor supply tightened Bronica bundled Zenzanon-branded normal lenses in place of the 75 mm Nikkor, the best known being the 80 mm f/2.8 MC Zenzanon made by Carl Zeiss Jena on a Biometar design. No blog or video review devoted to the EC was found; forum owners describe the EC series as smoother and quieter to fire than the S series, with the electronic shutter’s spare parts as the weak point, but none of those are reviews.

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.

Live listings

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 2026-11-02. Links go to the shop or marketplace that carries the item.

Related: Zenza Bronica S2A · Zenza Bronica EC-TL · Zenza Bronica EC-TL II · Zenza Bronica S2

Lenses for this body: Komura 100mm f/2 (Bronica) · Komura 100mm f/2.8 (Bronica) · Komura 135mm f/2.3 (Bronica) · Komura 150mm f/3.5 (Bronica) · Komura 200mm f/3.5 (Bronica) · Komura 200mm f/4 (Bronica) · Komura 300mm f/5 (Bronica, Unihelicoid) · Komura 400mm f/6.3 (Bronica, Unihelicoid) · Komura 45mm f/4.5 (Bronica) · Komura 500mm f/7 (Bronica, Unihelicoid) · Super-Komura 50mm f/3.5 (Bronica) · Nikkor-D 40mm f/4 (Bronica) · Nikkor-H 5cm/50mm f/3.5 (Bronica) · Nikkor-H·C 75mm f/2.8 'DX' (Bronica) · Nikkor-O 50mm f/2.8 (Bronica) · Nikkor-P 1200mm f/11 (lens head + Bronica focusing unit) · Nikkor-P 200mm f/4 (Bronica) · Nikkor-P 600mm f/5.6 (lens head + Bronica focusing unit) · Nikkor-P 75mm f/2.8 (Bronica) · Nikkor-P 800mm f/8 (lens head + Bronica focusing unit) · Nikkor-P·C 300mm f/5.6 (Bronica) · Nikkor-Q 105mm f/3.5 LS (leaf shutter, Bronica) · Nikkor-Q 13.5cm/135mm f/3.5 (Bronica) · Nikkor-Q 400mm f/4.5 (lens head + Bronica focusing unit) · Zenzanon 100mm f/2.8 · Zenzanon 150mm f/3.5 · Zenzanon MC 200mm f/3.5 · Zenzanon MC 200mm f/4 · Zenzanon 300mm f/4.5 · Zenzanon MC 40mm f/4 · Zenzanon MC 50mm f/2.8 · Zenzanon MC 75mm f/2.8 · Zenzanon MC 80mm f/2.4 · Zenzanon MC 80mm f/2.8 by Carl Zeiss Jena (Biometar)

Sources (5)

Every page here is assembled from public sources, and the gaps are real ones. If you own this camera, 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.