DxOMark published their sensor review and test results for Zeiss Loxia 50mm f/2 Planar T Lens (Sony E-mount). Tested on the Sony A7R, the Zeiss Loxia 50mm f/2 Lens gets 39 points DxOMark lens score and it has “very high levels of sharpness, and even at the initial aperture, center sharpness is excellent”.
Compared at the Sony Sonnar T* FE 55mm f/1.8 ZA Lens, the DxOMark writes:
The two are quite closely matched, though the Loxia’s astigmatism means that the performance in the outer field (the periphery) isn’t quite up to the Sony between f/2.8-8 — in other words, most of the usable aperture range. The Sony is also slightly better at f/2 in the corners at least, but at f/11 the Loxia is ahead slightly, yet that’s being really picky. In most other respects the two perform almost identically — that is, with the exception of chromatic aberration, where the Loxia is slightly better-corrected across the field.
Anyone looking for a small, high-grade 50mm lens for the Sony A7-series cameras will find a lot to like about the Zeiss Loxia. Not only is it relatively small and lightweight compared with other lens options such as the 55mm Otus (which could be used with an adapter), it is a very good performer, not to mention a lot more accessibly priced. It’s still not cheap, of course, and somewhat bizarrely, it competes directly with the similarly-priced Sony-made Zeiss-designed 55mm f/1.8 which not only is a slightly better performer in the outer field, but is an autofocus model, which may appeal to a wider market. Still, the Loxia is a great lens, but choosing between it and the Sony model may come down to whether you prefer manual focus or not.
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