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Mamiya Sekor C 500mm f/5.6 Manual Focus Lens for 645 {105}

Model #283236
  • $378.00

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New in box complete with manufacturer's USA warranty. Not previously owned or used.
Essentially new with no signs of use. “Open box.” In manufacturer's packaging with original accessories and instructions. 180-day warranty.
Barely used with virtually no traces of wear. Only the closest inspections will reveal slight use. Lens glass could contain light dust or debris. Excellent picture quality. Accessories usually not included, unless noted in listing. 180-day warranty.
Lightly used with limited signs of wear. Exceptionally nice but may have slight wear on finish visible. Lens glass could contain light dust or debris. Excellent picture quality. Accessories usually not included, unless noted in listing. 180-day warranty.
Noticeably used with average signs of wear. Shows moderate wear for the age of the item, with the possibility of blemishes and/or minimal dings. Lens glass may have average dust and zoom/focus ring tension may have slight looseness or tightness overall, but will not affect picture quality. Accessories usually not included, unless noted in listing. 180-day warranty.
Frequently used with above-average wear. May have dents, dings, or finish loss. Lens glass may have small scratches, dust, and blemishes, and zoom/focus ring tension may have moderate looseness or tightness overall, but should not affect picture quality. Accessories usually not included, unless noted in listing. 180-day warranty.
Heavily used with extensive visible wear. Equipment is rough, with multiple impressions in the finish, excessive finish loss and brassing. Glass will have marks, fungus and/or heavy/cloudy haze which could affect picture quality. Accessories usually not included, unless noted in listing. Not covered under KEH warranty.
Non-functional or damaged. Equipment will not work. Usable for parts. Not covered under KEH warranty and non-returnable.
EX Excellent
With Caps
$378.00
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Mamiya Sekor C 500mm f/5.6: serious reach for the 645 system.

A 500mm manual focus lens in the Mamiya 645 mount is a specialized tool. The f/5.6 maximum aperture gives you a workable shooting window at this focal length, and the Mamiya 645 system's medium format frame means you're working with a larger image circle than a 35mm telephoto of the same reach. Manual focus at 500mm demands discipline, slow subjects, precise technique, and a deliberate shooting approach.

For photographers already invested in the Mamiya 645 system, this lens extends the kit into long telephoto territory without switching systems. The Sekor C designation places it within Mamiya's dedicated 645 lens lineup, meaning full mechanical integration with compatible 645 bodies. At this focal length and format, the optical rendering carries the character that medium format glass is known for.

Who It's For

Wildlife and nature photographers shooting with a Mamiya 645 body who need 500mm of reach without leaving the system will find this a logical fit. Large-format sports or airshow shooters who prefer manual focus and slower-paced subjects can work with the f/5.6 aperture in good light. Collectors building out a complete Mamiya 645 Sekor C system will want it for the lineup. Photographers who shoot from a fixed position, blinds, stands, fixed sports angles, where manual focus at distance is practical than a liability.

Key Features

  • 500mm focal length for serious telephoto reach
  • f/5.6 maximum aperture for medium format telephoto
  • Mamiya 645 mount with mechanical integration
  • Manual focus operation
  • Sekor C-series optical design

FAQ

What mount does this lens use?
Mamiya 645 mount. It integrates mechanically with compatible 645 bodies.
Is this lens manual focus?
Yes. At 500mm, you'll need a steady hand and deliberate focus technique.
What's the maximum aperture?
f/5.6. Workable for a telephoto at this focal length, though it limits light gathering in dim conditions.
Why choose a 500mm in medium format over a 35mm telephoto?
The 645 frame gives you a larger image circle and the optical character medium format glass delivers at long reach.
Is this lens part of Mamiya's C-series lineup?
Yes. The Sekor C designation means it's part of Mamiya's dedicated 645 lens system.
SpecificationValue
Focal Length500mm
Max Aperturef/5.6
MountMamiya 645

This description was generated using AI based on KEH's internal product standards, product expertise, and knowing what customers care about most. While we strive for accuracy, details may vary by individual item.

Brand Name Mamiya
Focus Type Manual focus (only)
Lens Mount Mamiya M645
Lens Type Telephoto / Long
Max Focal Length 500mm
Min Focal Length 500mm