Mamiya 645AF (1999–today)

A medium format film camera with autofocus, built-in power winder and AE prism finder

Overview

The Mamiya 645AF is a medium format autofocus film camera system introduced in 1999. It uses the 6x4.5cm frame size and features a fixed prism viewfinder with 0.71x magnification. Designed as an evolution of the 645 Pro TL, it integrates a power winder and AE prism directly into the body for streamlined operation. The camera supports electronically controlled lenses via a new bayonet mount with electrical contacts, enabling autofocus driven by the camera body itself.

Ken Rockwell describes the autofocus action as sounding and feeling like a Nikon from 1988—functional but not fast. While he calls it a "slick" camera, he personally prefers the Contax 645 system. The 645AF was part of Mamiya’s push into autofocus medium format, sitting alongside models like the 645AFD and 645AFDII, though exact positioning within the lineup isn't specified.

Specifications

Production years	1999–today
Dimensions	142 x 152 x 134 mm
Weight	1554g
Shutter speed (max)	1/4000 sec
Flash sync speed	1/125 sec
Viewfinder	Fixed prism, 0.71x magnification
Lens mount	Mamiya 645AF bayonet with electrical contacts
Power source	6xAA batteries
Film back	LCD display with film type setting buttons

Design

The Mamiya 645AF uses a body-driven autofocus system, where focus is achieved through mechanical coupling initiated by the camera rather than the lens. The lens mount includes multiple electrical contacts to support AF communication and electronically controlled apertures. The shutter is a metal focal-plane type, and all core functions—including film advance and exposure metering—are integrated into the body without requiring external modules.

Product Family

The Mamiya 645AF shares design lineage with the 645 Pro TL, but adds built-in autofocus, power winder, and AE metering. It was compared by Mamiya to the later 645AFD and 645AFDII models, though specific hierarchy or improvements aren't detailed. The system includes specialized lenses such as the 300mm f/4.5 AF APO, which was the longest AF lens in Mamiya’s 645 lineup at its release.

Market

Originally priced at $3,800 in 2004, the 645AF now sells for significantly less on the used market. Ken Rockwell notes they are "very inexpensive used" today. However, users report ongoing challenges finding replacement batteries or external power packs, with some components like the PE401 battery pack listed as temporarily unavailable at major retailers.