A side note before reading on, my basis of this review will be from the Mamiya 645 AFD, as I have not had or used the AFD II which is between these two cameras.
The Phase One 645AF was the culmination between Phase One and Mamiya as Phase One bought Mamiya in 2009 and in doing so marketed the Phase One 645AF as a fully digital medium format where as Mamiya marketed the 645AFD III retaining the use of film. Other than marketing the cameras are both the same with nothing more than a different name badge and marketing plan.
As mentioned, the Phase One 645AF was marketed as fully digital however the body is able to accept film magazines and all Mamiya 645 lenses be it manual or auto focus making you able to use legacy lenses from past eras.
This camera came to my hands as an upgrade from the Mamiya 645 AFD, as it has a few more features and small changes that to me made a big difference. The biggest advantage for my use was the repositioning of the mirror lock up function. The former had a lever on the left hand side of the body and was moved to a location on the shutter release lock. This change allowed me to use an L-bracket which I use the majority of the time while shooting while maintaining the ability to use the mirror lock up function. Another difference is that the exposure compensation and exposure mode selector dials on the prism have been removed and allocated to buttons on the main body. making for a more ergonomic location for ease and quicker access during shooting.
Like its predecessor, the Phase One 645AF continues the use of a 6×4.5cm format giving a 4:3 ratio. Focussing screens are interchangeable and some will come with an outline that correlate with the crop factor of a digital back. As some digital backs have various sensor sizes one must take care that the focussing screen is suitable for the digital back you are going to be using should you do so.
As an overall, in comparison to my older Mamiya 645AFD the differences are subtle, all in all the main shape is pretty much the same. I don’t see or feel any difference in the ergonomics of grip or body shape. The specs between the two are minor as well with an upgraded autofocus and few other enhancements. The main difference is the placement of buttons and levers increasing the speed of the user to be able to switch options and functions on the fly.
On a personal note, when it come to 645 cameras this has now become my personal go to, I have up graded to digital with this model but i still retain and use the 120 film backs as back up or to use films with a higher ISO then what my digital back can handle.
The Specs:
Produced: 2009
Type of camera: Medium format Single Lens Reflex
Film/picture format: 120/220 film 6 x 4.5cm also compatible with Digital backs
Lens Mount: Mamiya/ Phase One
Lens(es): Interchangeable with Mamiya 645 mount lenses both manual and automatic focusing.
Shutter: Electronically controlled focal plane vertical shutter with speeds of 30 seconds to 1/4000 including Bulb.
Exposure metering: TTL metering, centre-weighted average (AV), spot (S), and variable ratio (A-S auto)
Viewfinder: Fixed eye level pentaprism viewfinder with 94% coverage
Focusing screen: Interchangeable with three screens
Reflex mirror: Yes, instant return with lock up available
Depth-of-field preview: Button found on body
Frame counter: Additive, found on LCD screen on camera body and film back
Film advance: Electronically controlled with a frame rate of 1.2 frames a second.
Power source: Six AA Batteries
Camera Back: Interchangeable film magazines, polaroid pack film, and digital backs.
Body Finish: Black plastic with metal alloy substructure.