Sony NEX with Mamiya 645 medium format lenses


The mirrorless camera is a relatively new breed of cameras that appeared in the market a few years ago with the Olympus PEN and the Panasonic Lumix GF1 (the 4/3 format). Small cameras with larger sensors than the so called compact ones with great image quality, interchangeable lenses and small size and weight. I personally invested after much research to the Sony NEX system which featured a APS-C 1.5x sensor in a extremely small body. I have used on this camera lenses from Leica, Voigtlander, Nikon and Yashica with great results. They are all 35mm format lenses and some of them transform the NEX to a superb quality camera.

When I discovered that there is an adapter for my Mamiya 645 lenses I immediately ordered it. Now, medium format lenses on a mirrorless camera, that’s something worth trying. My Mamiya 645 system (M645 Pro TL camera and 45,80,150 lenses) has not been used recently since I prefer the 6×7 and 6×9 format due to its larger size of course. So, why not have three more lenses for my NEX to choose from.


(Sony NEX 5N, Mamiya Sekor-C 45mm f2.8, Aperture used: f2.8)

When mounted on the NEX, my Sekor-C 45mm f2.8 lens looked huge. The adapter is also very big, so you get a strange looking combo with large size overall. Basically, you hold the lens and not the camera since the weight could probably do some damage if used for sometime (I don’t know that for sure of course, but I am not willing to find it out either !!!). The good thing is that my adapter has a tripod socket on it, so I can mount it safely on a tripod (with the 150mm lens for example that should be necessary if I want crystal clear images).

(Sony NEX 5N, Mamiya Sekor-C 45mm f2.8, Aperture used: f2.8)

(Sony NEX 5N, Mamiya Sekor-C 45mm f2.8, Aperture used: f2.8)

My first impressions are very good. I only had the time to use the Mamiya Sekor-C 45mm f2.8 on the NEX (all images on this post were taken with this lens), but I found the results very pleasing. Great color and detail and also great bokeh. Most of my shots were taken wide open at f2.8 and I really like the rendering of this lens on the NEX.

When 35mm lenses are used, the sensor will “see” the center of the lens which is a good thing since this is the best part of it. Now, with medium format lenses, the sensor will “see” again a very small portion of the whole lens, at it’s center of course. I am not technically proficient to say if it works the same way as a 35mm lens but from what I see the results are very good.

As always, I used the focus peaking of the NEX, but this time it was a little harder to focus, so I sometimes used the manual zoom function. I don’t know if it has something to do with the medium format lens but generally it was more difficult to nail focus than with my 35mm lenses. The good thing is that the focus ring of the Sekor 45mm is very precise (and for that reasons slower, the focus ring takes a lot to turn from 0.45m to infinity). The whole process makes it slower to work than with other lenses (the awkward size compared to the camera body results to worse ergonomics) but I don’t find that to be a problem for my kind of shooting.

(Sony NEX 5N, Mamiya Sekor-C 45mm f2.8, Aperture used: f8)

One other thing to mention is the focal length of my Mamiya lenses. On. My M645 camera the 45,80,150 focal lengths transform to 28-50-90, which I found it to be the best combination. On the NEX the equivalent is 67-120-225, so we are talking about a telephoto system. The 45mm could be used as a street & portrait lens, but I don’t think I would walk on the streets with this setup. On the other hand the 80mm could make an excellent portrait lens and the 150mm a great telephoto lens.
I will try to test both the 80 and 150 lenses as soon as I find the time.

My first conclusion is that I will probably take advantage of my Mamiya lenses on the NEX at situations I find appropriate. I would not invest in this setup if I didn’t already had the Mamiya lenses, but since the adapter is not expensive, I figured I could get some use for them. After testing the 80 and 150 lenses I will probably have a better view of the NEX/Mamiya setup.

All images below were taken with the Sony NEX 5N and the Mamiya Sekor-C 45mm f2.8






(c)2012 Konstantinos Besios. All rights reserved.

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8 Responses to Sony NEX with Mamiya 645 medium format lenses

  1. Anthony W says:

    Your images look great. May I know the name of the adapter and where to get it? Thanks!

  2. Anthony W says:

    Hi, I bought one from ebay. However, I notice that the lenses are only able to be used at wide open (i.e. taking pic at the largest aperture) because the one I bought could not control the actual aperture of the lense. Is your one able to really taking pictures at your chosen aperture?

    • kbesios says:

      I didn’t have any problems with this. I choose my aperture setting by rotating the aperture ring of the lens (the same way I do it with my Mamiya 645 Pro TL).

  3. Lynn says:

    How many times has your lens come off this adapter? I almost lost my lens three different times. I will not use this adapter again.

  4. Frank B. says:

    Did you test M645 lenses with the adaper for the Sony A7R ?

    • kbesios says:

      I do not own the A7R. The adapter I have for the NEX 5N works pretty well (same mount), now I don’t know how it will behave on a full frame sensor body.

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