Metabones Speed Booster Initial Impressions
See the previous announcement of the Metabones Speed Booster and the additional discussion.
The Sony NEX-6 digital camera showed up minutes before a trip to San Francisco to meet a friend, and so I hardly any chance to set it up or shoot it. But I did manage to snap some shots with the Canon EF 40/2.8 STM and the Canon EF 24mm f/2.8 IS.
Initial impressions:
- Image quality is exceptional in the center, with superb contrast, so much so that moiré shows up fairly easily— moiré is provoked in part by a very high micro contrast and extreme sharpness— this is the case. But there is also falloff away from center. I shot at f/5.6, which is stopped down three stops. Still, since I did not use manual focusing, I don’t even know how accurate the focus was other than it being very sharp at center in the resulting image.
- Lateral chromatic aberrations were seen with both the 40/2.8 and 24/2.8 IS, Adobe Camera Raw (ACR) correction is advised with those two.
- Perhaps distortion is also more visible than on full frame as the image is scaled down to fit APS-C.
- The NEX-6 had great difficulty with autofocus on these ultra high contrast buildings and similar targets. The focus would hunt in and out even on these buildings with their high contrast “lens target” patterns. Perhaps other lenses or camera models will operate more successfully.
Clearly, the choice of lens is important and some lenses will work better than others. Also bear in mind that lens weaknesses are visible with plenty of other 'native' lenses on Sony NEX (without the SpeedDoubler). So the comments above should not be construed as saying the results are less good than with (for example) a Sony zoom lens. In fact, the center area is at a very high level of performance unlikely to be equalled by most other lenses.
I have a lot of experimentation to do, including use of some fast lenses and some manual focus Zeiss and Nikon AI-S lenses, now that (tonight) I have the NEX-6 programmed the way I need it set up. It won’t be a major project, but I will be surveying a good selection.