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FotodioX Pro Lens Mount Adapter for Mamiya 645 Lens to Pentax K Mount Camera

BH #FOPPKAM645 • MFR #M645-PK-PRO
5 reviews
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FotodioX Pro Lens Mount Adapter for Mamiya 645 Lens to Pentax K Mount Camera
Key Features
  • Mamiya 645 to K Mount DSLR
  • Maintains Infinity Focus
  • Leaf Spring Mount Design
  • Brass with Stainless Steel Finish
This Pro Lens Adapter from Fotodiox enables the use of your Mamiya 645 lenses on Pentax K mount SLR and DSLR cameras. It features a durable brass construction with stainless steel finish, a leaf spring ensures a secure connection between the lens and adapter, and its design also maintains infinity focus.
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FotodioX M645-PK-PRO Overview

This Pro Lens Adapter from Fotodiox enables the use of your Mamiya 645 lenses on Pentax K mount SLR and DSLR cameras. It features a durable brass construction with stainless steel finish, a leaf spring ensures a secure connection between the lens and adapter, and its design also maintains infinity focus.

This manual adapter does not maintain automatic lens control between the camera and lens; aperture priority or manual shooting modes should be used, as well as stop-down metering for exposure control.
UPC: 847372010073

FotodioX M645-PK-PRO Specs

Item Type
1x Lens Mount Adapter
Camera Compatibility
Pentax K Mount
Lens Compatibility
Mamiya 645 Mount
Electronic Communication
No
Included Shims
Materials
Brass
Packaging Info
Package Weight
0.25 lb
Box Dimensions (LxWxH)
3.5 x 3.4 x 1.6"

FotodioX M645-PK-PRO Reviews

Perfect fitting adapter

By Ron
Rated 5 out of 5
Date: 2025-03-17

everything clicks into place as it should. I noticed the adapter focuses slightly beyond infinity. I think this is intentional as cameras and lenses vary a bit. Not focusing to infinity would be not good.

It works!

By Bruce
Rated 5 out of 5
Date: 2015-03-25

Very useful tool. I have a large selection of Mamiya prime lenses which are optically far superior to most 35mm/APS lenses. Along with a soft focus, this is just an amazing lens in itself. Please be very careful with this adapter, nothing wrong with it, but the Mamiya lenses are very heavy and place stress on the Pentax bodies. The bodies were not engineered for this weight, nor should they have been. Everything is manual, so slow down and enjoy the experience.

See any errors on this page?

question

will this adapter work on the K3II??
Asked by: Frank M.
Pentax cameras are legendary for using film camera lenses. Their method is keyed to setting the camera to Manual mode on the camera's rotary wheel. I can see absolutely no reason why the Fotodiox Pro M645-PK lens adapter will not work for Mamiya lenses but beware of very heavy lenses. The Pentax camera must also be set so that it can use its internal light meter to determine a shutter speed appropriate for a fixed f-stop and ISO value for the lens you have mounted. Since everything is going to be manual, you must do all the work and set the lens f-stop,camera ISO and lens focus. The Pentax camera must have two altered menu settings The Green button on the back of the camera will be used to let the internal light meter determine the shutter speed for the manual ISO and the lens f-stop of your choosing. You can determine the settings you want by trial and error.The Menu settings are first go to C-4 and set Using Aperture Ring to Enable.Next go to Camera-4 and E-Dial Programming then E-dial Programming-2.Set the M<>Tv PLine to TvSHIFT.After doing all of this, shut off your camera. Mount the Fotodiox and the lens of you choosing. Turn the camera back on and the camera will ask you for the focal length of your lens. Choose it and now you are ready to shoot.If you want to shoot video, I suggest the video setting TAv and a shutter speed of 1/60 sec. Of course you must manually focus and manually set your f-stop. The camera will set the appropriate ISO if not too low or too high.
Answered by: Don H.
Date published: 2018-08-28

question

Will this work on 645d? With mamiya 645m lenses?
Asked by: Matthew B.
This adapter allows your 645 manual lenses to fit a Pentax digital or film body
Answered by: David M.
Date published: 2018-08-28
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