Skip to product overview

Mamiya 90mm f/3.8 Sekor C Lens for RB67

The Mamiya 90mm f/3.8 is a 90mm f/3.8 lens designed for Mamiya RB mount cameras. Check GearFocus for current availability, with buyer protection on every purchase.

Mamiya 90mm f/3.8 Sekor C Lens for RB67

Mamiya 90mm f/3.8 Sekor C Lens for RB67

Get notified when one lists.

We'll text or email you the moment a Mamiya 90mm f/3.8 is listed on GearFocus.

Have a Mamiya 90mm f/3.8 sitting in your bag?

You'd be the first listing for this model.
Serious buyers are already watching — list yours in minutes.

Sell your Mamiya 90mm f/3.8 on GearFocus

Lens Overview — Mamiya 90mm f/3.8

The Mamiya 90mm f/3.8 Sekor C is a prime medium format lens built specifically for the Mamiya RB mount system. With a fixed focal length of 90mm and a maximum aperture of f/3.8, this lens sits comfortably in the standard focal length range for medium format photography, offering a natural perspective well-suited to a variety of shooting scenarios. Being a manual focus lens, it puts full control in the photographer's hands, which aligns naturally with the deliberate, methodical shooting style that medium format work typically demands.

The lens accepts 77mm filters, a generous thread size that reflects the optical scale of medium format glass. Weighing in at 820g, it has a substantial feel that is consistent with the build expectations of professional medium format equipment. There is no image stabilization, which is standard for lenses of this era and format.

For photographers already invested in the Mamiya RB system, this 90mm prime represents a practical and capable optic for medium format work, offering a fixed focal length that encourages compositional discipline and a maximum aperture of f/3.8 for controlled light management.

Key Features — Mamiya 90mm f/3.8

90mm Standard Focal Length: Provides a natural, undistorted perspective on medium format that translates roughly to a 45mm equivalent on 35mm, making it versatile for portraits, still life, and general photography.

f/3.8 Maximum Aperture: Offers usable light-gathering capability for a medium format prime, allowing for moderate subject separation and shooting in lower light conditions.

Mamiya RB Mount: Designed exclusively for the Mamiya RB67 system, ensuring full mechanical compatibility with the camera's rotating back and body functions.

Manual Focus Design: Puts full focus control in the photographer's hands, well suited to the deliberate, tripod-based workflows typical of medium format shooting.

77mm Filter Thread: Large filter diameter accommodates a wide range of professional filters including polarizers and ND glass scaled appropriately for medium format optics.

Leaf Shutter Lens: Houses a built-in leaf shutter that syncs with flash at all shutter speeds, a significant advantage for studio and daylight fill flash work.

Lens Specifications — Mamiya 90mm f/3.8

Mamiya 90mm f/3.8 full specifications
SpecDetail
Use CasesPortrait, Studio, Product
Lens TypePrime
FormatMedium Format
Zoom/PrimePrime
Focal Length90mm
Maximum Aperturef/3.8
Camera SystemMedium Format
Lens MountMamiya RB
AutofocusNo
Focus TypeManual
Image StabilizationNone
Filter Thread77mm

Description — Mamiya 90mm f/3.8

The Mamiya 90mm f/3.8 Sekor C is a prime lens built for the Mamiya RB mount, designed to work with the Mamiya RB67 camera system. It covers the medium format frame and offers a 90mm fixed focal length, placing it in the standard focal length range. With a maximum aperture of f/3.8, it delivers controlled exposure options in a variety of lighting conditions.

The lens is manual focus only, which suits the measured, precise approach that medium format photography typically calls for. A 77mm filter thread makes it compatible with a broad selection of professional filters. At 820g, the lens has a solid, substantial presence. Image stabilization is not included, which is in keeping with the design conventions of medium format optics from this era.

For Mamiya RB system users seeking a reliable 90mm prime, this Sekor C lens offers native mount compatibility and straightforward manual operation.

Pros — Mamiya 90mm f/3.8

  • ✓Prime 90mm focal length in the standard range is well-suited to medium format shooting
  • ✓Maximum aperture of f/3.8 provides reasonable light-gathering capability for a medium format prime
  • ✓Large 77mm filter thread accommodates a wide range of professional filters

Cons — Mamiya 90mm f/3.8

  • ✗Manual focus only — no autofocus support, which may slow down certain shooting workflows
  • ✗At 820g, the lens adds considerable weight to an already substantial RB67 body
  • ✗No image stabilization, though this is expected for a lens of this type and era

Videos — Mamiya 90mm f/3.8

Mamiya RB67 Pro SD - Long Term Review — Kyle McDougall

Resources & Downloads — Mamiya 90mm f/3.8

Manuals & Guides

Frequently Asked Questions — Mamiya 90mm f/3.8

Which camera systems is this lens compatible with?+
This lens is designed for the Mamiya RB mount, making it compatible with Mamiya RB67 cameras. It is not natively compatible with other camera systems without an adapter.
Does this lens support autofocus?+
No, the Mamiya 90mm f/3.8 Sekor C is a manual focus lens only. Photographers will need to focus by hand, which is typical for medium format lenses of this generation.
What filter size does this lens use?+
The lens has a 77mm filter thread, allowing you to use a wide selection of standard 77mm filters for creative or protective purposes.
How heavy is this lens?+
The lens weighs 820g. Keep this in mind when planning your kit, as it adds meaningful weight alongside the Mamiya RB67 body.
Does this lens have image stabilization?+
No, this lens does not include image stabilization. This is consistent with medium format lenses of its era, where tripod use is generally recommended.

Similar to Mamiya 90mm f/3.8

Loading similar products...