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

Mamiya-Sekor C 150mm f/3.5 (645)

Mamiya · Mamiya 645 · 1985

Also known as: Mamiya-Sekor C 150mm f/3.5 · Mamiya Sekor C 150mm f3.5 · Mamiya 645 150mm f/3.5 · Mamiya 150mm f/3.5 N · Mamiya Sekor C 150mm f/3.5 N · Sekor C 150/3.5 · マミヤ セコールC 150mm F3.5 · マミヤ 645 150mm F3.5 · セコール C 150mm F3.5 N

Variants & identification

Variant Mount Years Serial ranges Production
Mamiya-Sekor C 150mm f/3.5 (metal-barrel C version) Mamiya 645 — — —
Mamiya-Sekor C 150mm f/3.5 N Mamiya 645 1985 — —
  1. Optical construction, angle of view, minimum aperture, closest focus, magnification, filter size, hood, dimensions and weight are from Mamiya's own tables (the Sekor C instruction sheet at butkus.org and the 645 Interchangeable Lenses product sheet). The C version's 415 g is Wikipedia's figure, matched by Nordhaug's example.
  2. The family year is the N's: Mamiya's sheet ties the N lenses to the M645 Super, which Japanese Wikipedia dates to December 1985. The metal-barrel C f/3.5 is older but no source consulted dates it, and camera-wiki's original 1975 list shows only 150mm f/4 and f/2.8 lenses, so the true first year lies somewhere between 1975 and 1985 and is left unstated rather than guessed.
  3. Three other Mamiya 645 150s are separate lenses, not versions of this one: the early Sekor C 150mm f/4, the A 150mm f/2.8 (6 elements in 4 groups, 67 mm filter, 740 g) and the leaf-shutter A 150mm f/3.8 N/L (5 in 5, 67 mm, 620 g), all per Mamiya's product sheet. A Flickr 645 group thread's advice: the f/3.5 is 'the best balanced of the 150's and reasonably cheap'.
How to tell them apart (expand)
  • Two versions, same optics: the letter N after the focal length and a plastic rather than metal aperture ring are the documented differences
  • Built-in pull-out hood on both versions; Mamiya's sheet says the telephotos' hoods come out more smoothly if rotated while pulling
  • 58 mm filter thread and f/32 minimum aperture separate it from the f/2.8 and f/3.8 150s, which take 67 mm filters
  • No shutter-speed ring: the leaf-shutter 150 is the f/3.8 N/L, a different lens

Mamiya-Sekor C 150mm f/3.5 (metal-barrel C version):

  • No N after the focal length on the name ring
  • All-metal barrel with a built-in retractable hood; 415 g against the N's 420 g (Wikipedia; Nordhaug's C example weighs 415 g)
  • 5 elements in 5 groups, 1.5 m closest focus, 58 mm filter (Japanese Wikipedia)

Mamiya-Sekor C 150mm f/3.5 N:

  • N engraved after the focal length; plastic aperture ring of the second-generation lenses (Wikipedia)
  • Mamiya's table: 5 elements in 5 groups, 26° angle of view, f/3.5–32, 150 cm closest focus, 0.12×, 344 × 465 mm field, 58 mm filter, built-in hood, 80 × 70 mm, 420 g

Specifications

Construction
5 elements / 5 groups
Aperture range
f/3.5–f/32
Min. focus
1.5 m
Dimensions
70 × 80 mm
Weight
420 g
Filter
58 mm
Years manufactured
1985
Country
Japan
Coating
Multi-coated on both versions: Mamiya's sheet says 'all the lenses for the M645 have been multi-coated', and the C in Sekor C denotes multicoating (Wikipedia)

What reviewers say

Optical Ratings

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

Chromatic aberration
modest
Optical formula

Mamiya's two lens sheets consulted (the Sekor C instruction sheet at butkus.org and the 645 Interchangeable Lenses product sheet) tabulate 5 elements in 5 groups but print no cross-section, and no other Mamiya document with a diagram for this lens was found.

History

The 150mm f/3.5 is the plain telephoto of Mamiya’s manual-focus 645 line, a 93mm equivalent on 35mm film by Mamiya’s table, and the cheapest of four 150s the system offered. Mamiya’s own figures: 5 elements in 5 groups, a 26° angle of view, f/3.5 to f/32, closest focus at 150 cm for 0.12×, a 58 mm filter thread, a built-in pull-out hood, and 420 g in a barrel 70 mm across and 80 mm long. The design type is not named in any Mamiya document consulted and no cross-section was found.

Two versions exist and the optics do not change between them. The metal-barrel Sekor C came first: Japanese Wikipedia lists it with the same 5 in 5, 1.5 m and 58 mm as the later lens, and Wikipedia gives it 415 g. When it appeared is not recorded anywhere consulted. Camera-wiki’s list of the original 1975 lenses has a 150mm f/4 and a 150mm f/2.8 but no f/3.5, so it seems to have arrived later in the M645 years, and Tim Dobbs’s Emulsive review of the 1000S is still shooting the f/4. The Sekor C N followed in 1985: Mamiya’s instruction sheet says the N lenses were developed for the M645 Super and fit the earlier bodies, and Wikipedia describes the N as a restyled barrel with a plastic aperture ring. Because the C is undated, this page carries the N’s year as the family’s, and the table note says so.

The verdicts are consistent and moderate. Teo Totev tested two copies on a Phase One DF with a Leaf Aptus 75 and got the same result from both, sharpness 6 and bokeh 6, a tier below the 110mm f/2.8 he scores 9 for sharpness. Dag Ole Nordhaug, on a 100-megapixel Hasselblad X2D, found the centre ‘a bit soft’ and the corners ‘very good’, with modest chromatic aberration, and kept it for hiking because of its weight and a focus ring he ranks among the best he has used. Lensvana calls it ‘not as refined’ as the f/2.8 A but good for the price. A Flickr Mamiya 645 group thread sums up the choice among the 150s: the f/3.5 ‘unless you need the speed of the f2.8, small size of the f4 or flash sync of the f3.8’.

Those three siblings are the buying trap. The A 150mm f/2.8 is a 6-element lens at 740 g with 67 mm filters; the A 150mm f/3.8 N/L carries a leaf shutter, also with 67 mm filters, at 620 g; the early f/4 is a smaller lens still. A 58 mm thread and an f/32 minimum aperture identify the f/3.5. It also mounts on the 645AF, AFD and DF bodies, but Wikipedia notes it then meters only stopped down. On any example, check that the hood slides freely, that the Auto/Manual lever is back on A (Mamiya’s sheet warns that leaving it on M gives wrong exposure), and that the aperture blades snap shut.

What remains open: the year the C-barrel f/3.5 was introduced, a launch price in any currency, a discontinuation date for the N, and whether Mamiya ever changed the coatings between the two versions.

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 taken with the Mamiya-Sekor C 150mm f/3.5 (645)
Mamiya-Sekor C 150mm f/3.5, side view (Gürkan Sengün) — Gürkan Sengün, via Wikimedia Commons (CC BY-SA 3.0)

Sample photo wanted — shot with a Mamiya-Sekor C 150mm f/3.5 (645)? We'd love to feature it (with credit).

Live listings

Asking price, USD: a median of $180 across 48 fixed-price listings on 2026-09-19 (middle half $150–$210). First day tracked.

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

Show 89 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 C 110mm f/2.8 (645) · Mamiya-Sekor C 45mm f/2.8 (645) · Mamiya-Sekor C 55mm f/2.8 (645) · Mamiya-Sekor C 80mm f/1.9 (645) · Mamiya-Sekor C 80mm f/2.8 (645)

Sources (10)

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.