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

Mamiya-Sekor 55mm f/4.5 (C-series TLR)

Mamiya · Mamiya TLR · 1968

Also known as: Mamiya-Sekor 55mm f/4.5 · Mamiya Sekor 55mm f4.5 · Mamiya TLR 55mm f/4.5 · Mamiya C330 55mm f/4.5 · Mamiya C220 55mm · Mamiya 55mm blue dot · Sekor 55/4.5 TLR · マミヤ セコール 55mm F4.5 · マミヤ C330 55mm · マミヤ 二眼 55mm

Variants & identification

Variant Mount Years Serial ranges Production
Sekor 55mm f/4.5, black Seiko shutter, no aperture click-stops (1968 baseline) · Seiko, 1s–1/500 and B, M/X sync Mamiya TLR 1968–1980 — —
Sekor 55mm f/4.5, Blue Dot (click-stopped aperture, later Seiko shutter) · Seiko (later type with raised-tip leaf), 1s–1/500 and B, M/X sync Mamiya TLR 1980–1994 — —
  1. Optical construction, picture angle, minimum aperture, filter and hood diameters, closest focus, reproduction ratio, weight and flash sync are from Graham Patterson's Mamiya TLR System Summary (June 2015 release), which compiles Mamiya's own literature; Japanese Wikipedia agrees on 7群9枚, 0.241 m and φ46. English Wikipedia gives 330 g against Patterson's 360 g, and he notes his weights may include caps.
  2. Version boundaries are Patterson's Early/Middle/Late groupings by engraving and click-stops, not dated Mamiya changes: centimetre engraving on the earliest black lenses, millimetres without click-stops through the 1970s, click-stops from around 1980. The 1980 split used here is his 'around 1980' and should be read loosely; a shutter replaced in repair can carry the later click-stop type.
  3. No launch price in any currency was found for this lens.
How to tell them apart (expand)
  • Black barrel and black Seiko shutter on every 55; a chrome-bezel Seikosha shutter means a different focal length
  • Nine elements in seven groups, the most complex lens in the C-series range, in a lens that weighs about 360 g
  • 46 mm filter thread (the 65mm takes 49 mm with chrome keeper rings; the 55 does not have them)
  • Fits every C-series body with a lens board, including the auto-cocking C33, C330, C330f and C330s; the finder needs the 55/65 correction insert and the parallax dial set to 80mm (Patterson)
  • The RB67's Sekor C 55mm f/4.5 is a different lens with a 77 mm filter thread (Japanese Wikipedia)

Sekor 55mm f/4.5, black Seiko shutter, no aperture click-stops (1968 baseline):

  • All-black Seiko shutter with the speed and aperture scales read against one index on the left, a wide knurled speed ring and an aperture knob on the right (Patterson)
  • No click-stops on the aperture and no blue insert in the cocking lever: Patterson's 'Early' and 'Middle' black lenses; the earliest black lenses had the focal length in centimetres, the 1970s ones in millimetres
  • 46 mm filter thread on both lenses; 48 mm slip-on hood

Sekor 55mm f/4.5, Blue Dot (click-stopped aperture, later Seiko shutter):

  • Blue insert in the tip of the shutter cocking lever, which Patterson says usually indicates the newer shutter with a raised leaf tip meant to stop the blades locking as they close
  • Aperture click-stops at the full stops: Patterson's 'Late' group, from around 1980; focal length engraved in millimetres
  • Same 9-element optics, 46 mm filters, 24 cm closest focus and 360 g as the earlier black lens

Serial-range notes

103xx – 805xx (examples)
Patterson's tabulated 55mm serials run from 103xx to 805xx, all black-series lenses. Mamiya told him it has no dating information based on serial numbers; the only period evidence is the gold two-letter sticker some lenses carry (55mm codes AA, AG, AI, AK, CA, CF, CH, CI, DH, FD, JA, JE, JK among others), and he reads JE (377xx–378xx) as no blue insert and no click-stops, CI and DH as non-blue early-1980s lenses, CF as 1985 and FH as late.

Specifications

Formula
Retrofocus wide-angle, 9 elements in 7 groups (Patterson; Japanese Wikipedia 7群9枚)
Construction
9 elements / 7 groups
Aperture range
f/4.5–f/22
Shutter
Seiko leaf shutter in the taking lens, 1s–1/500 and B, M and X sync, flash at every speed; black series only, no Seikosha version
Min. focus
0.24 m
Weight
360 g
Filter
46 mm
Years manufactured
1968–1994
Country
Japan
Coating
Single-coated; Patterson names the 55 among the late black lenses that may have received multi-coating, with no evidence of when

What reviewers say

Optical Ratings

Aggregated from the reviews above — follow the links for the full picture.

Vignetting
negligible
Distortion
mild barrel

History

The 55mm f/4.5 is the widest lens Mamiya made for its interchangeable-lens twin-lens reflexes, and the only wide-angle in the range that was never sold in a chrome Seikosha shutter. It belongs to the black series: an all-black Seiko shutter with speeds from 1 second to 1/500 plus B, M and X flash sync, and a matched viewing lens above it on the same board. Graham Patterson’s system summary, which compiles Mamiya’s literature, gives 9 elements in 7 groups, a 70°30’ picture angle, f/4.5 to f/22, a 46 mm filter thread and 48 mm hood, closest focus at 24 cm for a 6.4 cm square field at nearly 1:1, and about 360 g. Japanese Wikipedia agrees on the construction, the 0.241 m and the 46 mm; English Wikipedia’s 330 g is the one discordant figure. Patterson likens it to a 24mm on 35mm film for a square print, or 36mm when a 2:3 crop is taken from the negative.

When it appeared is less tidy than it looks. Williams Photographic dates it to the C220 of 1968. Patterson finds the 55 and the 250 in an American distributor’s catalogue of 30 March 1967, calls actual availability unknown, and places the black series as a whole with the C220 and C330 around 1969. Its versions are Patterson’s groupings rather than Mamiya’s: the earliest black lenses carry the focal length in centimetres, the 1970s lenses in millimetres without aperture click-stops, and from about 1980 the aperture clicks at the full stops and a blue insert appears in the cocking lever, the ‘blue dot’ of the listings. He explains the insert as the mark of a later shutter with a raised leaf tip that resists the blades locking as they close, a shutter change rather than an optical one. The 55 is one of four lenses Patterson names as likely to have picked up multi-coating late, with no evidence of when. Some are labelled Seiko-SLV instead of Seiko.

Reviewers like it more than its f/4.5 suggests. Ashley Pomeroy, shooting one on a fifty-year-old C3, finds it sharp in the centre wide open with murky extreme corners, clean from f/8 and ‘basically razor-sharp across the frame’ at f/11, with mild barrel distortion and no vignetting worth mentioning; he calls it the easiest and cheapest route to wide-angle 6×6. Anton McCloud’s 35mmc verdict on the whole range is that every lens is excellent and some find them clinical next to Zeiss. Mamiya TLR Flickr group members describe the stretching of shapes at the edges that any rectilinear 55 on 6×6 produces and warn that it flares unless the sun is behind the camera, so the hood earns its place. Ian Bartlett’s Emulsive C220 review has it on his list to buy for landscapes, noting the 24 cm close focus.

Buying one means checking the shutter more than the glass. Set 1 second and listen for the escapement; Mamiya America told Patterson in 1999 that parts for the early Seiko shutters were exhausted. Make sure the cocking lever is on the correct side of the body’s cocking arm before mounting on a C33, C330, C330f or C330s, because a lens changed with the film part-wound can be damaged. Look for dented filter rings, the commonest fault Patterson records, and for the small finder correction plate the 55 needs: the bodies’ parallax and exposure scales stop at 80mm, so the 55 uses the 80mm setting plus the supplementary 55/65 insert. Serial numbers say nothing; Mamiya has no date table, and the only period clue is a gold two-letter sticker if it survives.

What remains open: the first year of sale (1967 catalogue, 1968 with the C220, or 1969 with the black series), a list price in any currency, whether any 55 was actually multi-coated, and the serial or date at which click-stops and the blue insert arrived.

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

Sample photo wanted — shot with a Mamiya-Sekor 55mm f/4.5 (C-series TLR)? We'd love to feature it (with credit).

Live listings

Asking price, USD: a median of $270 across 16 fixed-price listings on 2026-09-19 (middle half $230–$290). First day tracked.

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

Show 28 more 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 2026-09-19. Links go to the shop or marketplace that carries the item.

Related: Mamiya-Sekor 105mm f/3.5 (C-series TLR) · Mamiya-Sekor 180mm f/4.5 (C-series TLR) · Mamiya-Sekor 80mm f/2.8 (C-series TLR)

Sources (9)

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.