Komura 100mm f/2.8 (Bronica)
Sankyo Koki · Bronica S · 1965 · 5 elements in 4 groups
single source, unconfirmedAlso known as: Komura 100mm f/2.8 Bronica · Komura 100mm F2.8 for Bronica · Sankyo Koki Komura 100mm f/2.8 · Sankyo Kohki Komura 100mm F2.8 Bronica · Auto Sankyo Kohki 100mm f/2.8 Bronica S2A · KOMURA 100mm F2.8 For BRONICA · Komura 2.8/100 Zenza Bronica S2A · コムラー 100mm F2.8 ブロニカ · 三協光機 コムラー 100mm F2.8 · ゼンザブロニカ用 コムラー 100mm F2.8
Variants & identification
| Variant | Mount | Years | Serial ranges | Production |
|---|---|---|---|---|
| Komura 100mm f/2.8 for Bronica, automatic diaphragm | Bronica S | — | — | — |
- Element and group count, automatic diaphragm and 62 mm filter are from Japanese Wikipedia's Komura table alone; camera-wiki and Monaghan's list name the lens without specifications. No weight, length, minimum focus, blade count or minimum aperture has been published.
- Date: no source dates this lens. Seiden's history on Monaghan's page puts the Komura line at 1965–66 but lists the 45, 50, 135, 150, 200, 300 and 500 mm lenses and not a 100 mm; the year given here is the line's, and the lens may have come a little later, like the 100mm f/2 that Modern Photography pictured in November 1967.
- Monaghan's two entries, '100mm f2.8 Komura' and '100mm f2.8 Auto Sankyo Kohki', are taken here as one lens listed under its brand and under its maker's name: the second came from a 1998 sale advertisement, and Sankyo Kohki is the engraving that appears beside Komura on the Bronica lenses.
How to tell them apart
- Engraved Komura and Sankyo Kōki (Sankyo Kohki), on a Bronica small-bayonet mount with an automatic diaphragm, 62 mm filter thread
- Not the Zenzanon 100mm f/2.8, Bronica's own lens of the length, which takes 67 mm filters and carries the Zenzanon name; not the Komura 100mm f/2, a stop faster and engraved 1:2
- Not the Komura 105mm f/2.8 for Nikon S or Leica thread, a rangefinder lens with a coupled focusing mount of its own; the Bronica lens has no helicoid, only a bayonet head for the camera's focusing unit
Komura 100mm f/2.8 for Bronica, automatic diaphragm:
- Automatic diaphragm on the Bronica small bayonet, mounted on the front of the focusing helicoid (Japanese Wikipedia's lens table)
- 62 mm screw-in filter, the smallest in the Komura range for the Bronica and smaller than the 67 mm of Bronica's own Zenzanon 100mm f/2.8 (Japanese Wikipedia; Monaghan on the Zenzanon)
- Komura 100mm f/2.8 for Bronica, automatic diaphragm: The only version recorded. Japanese Wikipedia gives five elements in four groups, an automatic diaphragm and a 62 mm filter. Monaghan's list carries it twice, once as '100mm f2.8 Komura' and once as '100mm f2.8 Auto Sankyo Kohki' from a 1998 advertisement of a lens for the S2A, which read the maker's name rather than the brand; nothing shows two different lenses. Undated: Seiden's 1965–66 history of the Komura line does not include it.
Specifications
- Formula
- 5 elements in 4 groups
- Construction
- 5 elements / 4 groups
- Aperture range
- f/2.8
- Filter
- 62 mm
- Country
- Japan
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 Komura 100mm f/2.8 was Sankyo Koki’s short telephoto for the focal-plane Bronica, a length Bronica itself filled only with the Zenzanon 100mm f/2.8 of the later 1960s and the leaf-shutter Nikkor-Q 105mm f/3.5. Japanese Wikipedia’s Komura table gives it five elements in four groups, an automatic diaphragm and a 62 mm screw-in filter, the smallest front in the Komura range and smaller than the 67 mm thread that Bronica standardised on its own lenses. The automatic diaphragm places it on the small bayonet at the front of the Bronica focusing helicoid, so it fits every focal-plane body from the Z/D to the EC-TL II. No other figure has been published.
It is undated. Seiden’s history of the Bronica lenses, as given on Monaghan’s page, puts the Komura line at 1965–66 and says the lenses were marketed by the US importer and never appeared in Bronica’s Japanese literature, but its list of Komura lenses runs 45, 50, 135, 150, 200, 300 and 500 mm and has no 100 mm at all; the 100mm f/2 Komura was photographed on a Bronica for Modern Photography in November 1967, and the f/2.8 may belong to the same slightly later batch. Monaghan’s consolidated list carries the lens twice, once under its brand and once as the “100mm f2.8 Auto Sankyo Kohki” of a 1998 sale advertisement, the maker’s name read off the barrel where the seller did not know the brand.
No review of the lens has been found. It appears on the market more often than the Komura 100mm f/2, usually offered as a Komura or Sankyo Kohki 100mm f/2.8 for Bronica S2 or S2A, and the 62 mm filter is a quick check against the Zenzanon of the same length and speed.
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
Sample photo wanted — shot with a Komura 100mm f/2.8 (Bronica)? We'd love to feature it (with credit).
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