Last night I hit the town to test out the Metabones Speed Booster on my Sony NEX-5n with some old Nikon manual lenses. For the uninitiated, the Speed Booster is the “Holy Grail” adapter that allows any NEX camera to accept full-frame Canon EF lenses and utilize their full width and brightness (a gain of 1 f-stop of light). By reducing the size of the image circle, it essentially negates the crop factor of APS-C cameras. While the math can get confusing, the results are not: your full-frame lenses are as wide and bright on a NEX camera as they would be on a camera like the Canon 5DMKIII.
Almost. You’re actually getting a 1.09x crop factor, but considering the original crop factor of the camera would have been 1.5x, I’m not complaining. And you can’t complain about the size:
Sony NEX-5n + Speed Booster + Nikon 50mm f/1.8 pancake
The lenses I tested were the Nikon 24mm f/2 and Nikon 50mm f/1.8 pancake. I use Nikon lenses because they are plentiful, sharp, cheap, and compatible with almost any camera body. To fit them on the Speed Booster, I used an additional adapter ring.
Nikon to Canon EF Adapter
With this ring, you’re going from NEX to EF to Nikon. In theory this type of adaptation could also work with almost any other type of lens, provided it doesn’t have rear-protruding elements that would scratch the Metabones adapter or short out the electrical contacts. According to Metabones, dangerous lenses to watch out for include:
– Some M42 Screw-Mount Lenses
– OM 28/2.8
– OM 50/1.8
– Leica R 15/3.5
If you own these or similar lenses, definitely take precautions before using them with the Metabones Speed Booster. Otherwise you’ll void your warranty if you damage it.
In my in-field experience, shooting with the adapted Nikons worked just as advertised. My 24mm was wide and bright, and my 50mm was equally bright with a small footprint and lots of bokeh.
A few caveats:
– The lenses will focus past infinity with the Fotodiox adapter. I have not tested other brands.
-The Fotodiox ring tends to stick to the lens, so my advice is to just leave it on. Get one adapter ring per lens. They’re only about $15 apiece.
– According to other reviewers, you will experience vignetting with extreme wide angle lenses, and you will experience softness and chromatic aberration with lenses longer than about 85mm.
Other than that, I enjoyed the wider, brighter field-of-view with the adapter. Feel free to ask questions in the comments or request other types of testing.