Mamiya-Sekor Zoom C 75-150mm f/4.5 (645)
Mamiya · Mamiya 645 · 1975
single source, unconfirmedAlso known as: Mamiya-Sekor Zoom C 75-150mm f/4.5 · Mamiya Sekor C 75-150mm f4.5 · Mamiya 645 75-150mm f/4.5 · Mamiya 75-150mm f4.5 zoom · Sekor C 75-150/4.5 · Mamiya M645 75-150 · マミヤ セコールC ズーム 75-150mm F4.5 · マミヤ645 75-150mm F4.5
Variants & identification
| Variant | Mount | Years | Serial ranges | Production |
|---|---|---|---|---|
| Mamiya-Sekor Zoom C 75-150mm f/4.5 | Mamiya 645 | 1975 | — | — |
- Construction (11 in 10), closest focus (1.8 m) and filter thread (77 mm) are agreed by Japanese Wikipedia and the English Wikipedia table. The f/32 minimum, eight blades, slip-on hood, dimensions (114 × 84 mm) and weight (975 g) come only from the English table, so the page carries the single-source flag; Mamiya's Sekor C sheet prints its specification table as an image.
- No source consulted dates the lens. The year is the C line's start with the M645 (June 1975, Japanese Wikipedia); camera-wiki files it with the original C lenses, Mamiya's Sekor C sheet of the 645 Super years describes it, and the 645 Pro TL book of 1997 lists the 55-110 N and ULD 105-210 zooms only.
- Three other Mamiya 75-150s or near neighbours are different lenses: the Zoom C 55-110mm f/4.5 N and ULD 105-210mm f/4.5 of the later manual-focus line, and the autofocus Sekor Zoom AF 75-150mm f/4.5 D of 2007 for the 645 AF bodies, which shares the range and the aperture and nothing else. AF titles are excluded from this page's listings.
How to tell them apart
- Zoom C on the name ring with 75-150mm; the 105-210 is the longer original zoom and the 55-110 N the later wide one
- 77 mm thread and a slip-on hood: the 55-110 N and 105-210 take 67 mm and 58 mm
- One version only, C with no N; a 75-150 marked AF or D is the autofocus lens for the 645 AF bodies
Mamiya-Sekor Zoom C 75-150mm f/4.5:
- Name ring reads Mamiya-Sekor Zoom C 75-150mm 1:4.5 with nothing after the aperture; the only version, so no N is recorded
- 77 mm filter thread with a slip-on hood; 114 mm long, 84 mm across, 975 g (Wikipedia table)
- Constant f/4.5 to f/32, eight aperture blades, closest focus 1.8 m (Wikipedia table; Japanese Wikipedia agrees on 1.8 m and φ77)
- Separate zoom and focus rings: Mamiya's Sekor C sheet describes focusing at 150mm and then zooming out to compose
- Mamiya-Sekor Zoom C 75-150mm f/4.5: The first of the manual-focus 645's zooms, listed with the 105-210mm f/4.5 among the original C lenses by camera-wiki and described with it in Mamiya's Sekor C instruction sheet as suitable for both portraits and telephotography. No source consulted dates it; the year is the C line's start in 1975. The 645 Pro TL book of 1997 lists only the 55-110 N and the ULD 105-210, so this lens had gone by then. The autofocus Sekor Zoom AF 75-150mm f/4.5 D of the 645 AF years is a different lens on a different mount.
Specifications
- Formula
- 11 elements in 10 groups (Japanese Wikipedia 10群11枚; Wikipedia table)
- Construction
- 11 elements / 10 groups
- Aperture range
- f/4.5–f/32
- Diaphragm blades
- 8
- Min. focus
- 1.8 m
- Dimensions
- 84 × 114 mm
- Weight
- 975 g
- Filter
- 77 mm
- Years manufactured
- 1975
- Country
- Japan
- Coating
- Multi-coated: Mamiya's Sekor C sheet says all the lenses for the M645 have been multi-coated, and the C in Sekor C is Mamiya's multicoating mark (Wikipedia)
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 Zoom C 75-150mm f/4.5 is the first zoom of Mamiya’s manual-focus 645 system, a 47 to 93 mm equivalent on 35mm film that spans the 80 standard and the 150 short telephoto in one barrel. Japanese Wikipedia and the English Wikipedia table agree on 11 elements in 10 groups, a closest focus of 1.8 m and a 77 mm filter thread; the English table adds a constant f/4.5 to f/32 with eight blades, a slip-on hood, 114 mm by 84 mm and 975 g, which makes it heavier than the later 55-110 N by about 200 g. Mamiya’s Sekor C instruction sheet pairs it with the 105-210mm f/4.5 as lenses suitable for both portraits and telephotography, and recommends the zoom as a focusing aid: turn to 150mm, where the subject is large and the depth of field shallow, focus, then zoom out to compose.
It has one version and no date. camera-wiki lists it with the 105-210 among the original C lenses, Mamiya’s sheet of the 645 Super years still describes it, and the 645 Pro TL instruction book of 1997 lists only the Zoom 55-110mm f/4.5 N and the Zoom ULD 105-210mm f/4.5, so it had gone by then. The year carried here is the C line’s start with the M645 in June 1975, a floor. No N barrel is recorded by any source consulted, which fits camera-wiki’s newer list, where the only zoom is the 55-110 N. Thirty years later Mamiya reused the range for the autofocus Sekor Zoom AF 75-150mm f/4.5 D of the 645 AF bodies, a different lens on a different mount, and that is the one most search results now return.
No review of this lens was found by the searches made for this page. What the documents show is a two-ring zoom from the first years of the system, computed before Mamiya’s ULD glass, and a weight that puts it close to a kilogram on a body already heavier than most 35mm SLRs.
When buying, work the zoom and focus rings separately through their travel, since old grease stiffens the zoom first, and watch the image at 150mm while focusing to check that the lens holds focus when zoomed back to 75mm. Check for haze between the many groups, that the A/M lever returns to A, and that the slip-on hood is the right one. Read the name ring: Zoom C is this lens, and a 75-150 marked AF or D is the autofocus lens, which will not mount on the manual-focus bodies. What remains open: the launch and discontinuation years, a list price in any currency, and any independent test.
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 Zoom C 75-150mm f/4.5 (645)? We'd love to feature it (with credit).
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