Simmod Mamiya 645 Lens to Canon EF Camera Adapter with P-Lock

The Simmod Mamiya 645 to EF Adapter is a precision-machined adapter designed to mount Mamiya 645 lenses onto Canon EF and EF-S camera bodies while maintaining proper registration distance and optical alignment.

Mount Interface

• Lens mount: Mamiya 645
• Camera mount: Canon EF / EF-S

The adapter installs between the lens and camera body, allowing Mamiya 645 lenses to operate on EF-based systems without permanent modification to the lens.

Mechanical Design

The adapter is designed around a fixed mechanical structure intended to maintain alignment and minimize movement during operation.

• Secure Mamiya 645 lens interface
• Fixed EF mount connection
• Reduced rotational play and mount movement
• Designed for use with manual focus and cine-modified lenses

Construction

• Precision-machined metal construction
• Matte black internal finish to reduce reflections and stray light
• CNC-machined components for dimensional consistency and fit accuracy

The structure is designed to maintain rigidity while supporting larger medium format lenses.

Mechanical Performance

• Maintains proper registration distance for Mamiya 645 to EF conversion
• Supports infinity focus
• Preserves optical alignment between lens and sensor
• Provides a stable mechanical interface during operation

System Behavior

• Fully mechanical adapter
• No electronic communication or metadata transfer
• Manual focus and manual aperture operation only
• Does not alter optical characteristics of the lens

Installation

• Mamiya 645 lens mounts directly into the adapter
• Adapter attaches to EF camera body using standard EF bayonet interface
• No permanent modification to the lens required

Notes

• Designed specifically for Mamiya 645 lenses and Canon EF camera systems
• Intended for manual lens operation
• Proper support is recommended when using heavier medium format lenses