Without doubt, mirrorless cameras, except the Samsung NX series, with a flange focal distances of 25.50mm, are the most adaptable cameras to use on manual focus lenses. The Samsung's 25.50mm thickness was just enough to shut out the use of adapting Leica-M lenses, which many have said as one of the biggest disappointments. Leica M lenses are considered the pinnacle of 35mm lenses. The build and optical quality is unequaled in the 35mm lens world.
So, what lenses can be used on Micro 4/3 and E-Mount cameras?
In a word, pretty much all lenses existed on the 35mm format, if anyone is willing to make the adapter for a particular lens mount. The very short flange focal distance of the M4/3 (19.25mm), E-Mount (18mm), Fuji X (17.70mm) provide the opportunity to use a wide range of optical lenses, 35mm format, medium format, C-mount cine lenses, enlarging lenses, projection lenses, etc. The possibilities are practically endless. The only question is: is a mount adapter available?
The most popular lenses to use on M4/3 and E-Mount are Leica Thread Mount (LTM), Leica M mount and C-Mount. The reason is that these lenses have very short flange focal distance and therefore adapters can be made very thin. Adapted lenses would look very small, to complement the small M4/3 and NEX cameras. The quality of lenses are also some of the best in these mounts (except c-mount, where there is a big variance). To compare, the M mount adapter for NEX is roughly 10mm for the NEX, whereas the M42 to NEX adapter is almost 30mm thick. Even a pancake Contax 45mm f2.8 lens will look like a 85mm SMC Takumar when mounted on the NEX. Take a look at the comparison pictures below:
Voigtlander 40mm f1.4 & Contax 45mm f2.8 Pancake compared with and without adapter.
On adapters: C-Mount Switar 50mm f1.4, M-Mount Voigtlander 40mm f1.4, QBM 50mm f1.8
As you can see, the mount makes a big different on how large the lens will look when mounted on the camera. Even a normal, small 50mm f1.8 QBM lens will look huge when mounted on the NEX, but the C-Mount and M Mount lenses look nice and small.
A note on c-mount lenses. There are so many different lenses on this mount with different sizes. Be very careful what you are looking for in c-mount lenses. Some will not cover the image circle of the NEX or even M4/3 sensor, and some are too large to be used and be able to focus to infinity. Even those that mount and focus to infinity with full image circle coverage, the image quality may not be what you are looking for. The allure of c-mount lenses are their cinematic quality, or quirky characteristics, or weird bokeh or some combination of these or more. Make sure you know what you want. Some of these lenses costs thousands of dollars!
Another benefit of short flange focal distance of these mounts, is that the traditionally macro-only use of the enlarging lenses and projection lenses can be used like a normal lens; that is, be able to focus to infinity. I have done quite a bit with both the enlarging and projection lenses. If you do a search on my blog, you will see many examples.
In our next and final installment, Part IV, we will talk about buying manual focus lenses, what to look out for, why some lenses costs thousands and others almost nobody wants at give away prices, and the costs of different adapters.