SLR Gear, an offshoot website of the Imaging Resource, one of the web's most-trusted resources for all things digital photography, has just posted an in-depth review of the new Sigma 50 f1.4 Art lens, which the company bills as being a direct rival to the $4000+ Zeiss Otus.
So, does the Sigma live up to its billing? Short answer: yes.
Optically, the lens is really good. In terms of sharpness, the lens is good right from the get-go at f1.4. On sub frame, f1.4 is sharp corner to corner and only exhibits a little softness in the corners on FF. Remedy/ Stop down to f2 to reduce the problem and f2.8 to eliminate it. From then on, the lens remains extremely sharp, only losing a little sharpness due to the diffraction limit at minimum aperture, f16. As for chromatic aberration and distortion, both are very well controlled and should not present any real problems in real-life shooting. Vignetting? Being a f1.4 optic, it's there but is controlled to under a stop of falloff on full frame, a truly impressive feat for such a lens.
Mechanically, the lens is built in line with the other global vision models, as in like the proverbial tank. For materials, the lens uses a metal mount and a barrel of Sigma's patented Thermally Stable Composite (TSC), which, according to SLR Gear, has the feel of metal. The lens features a wide 1.5 inch, rubberized focus ring. Additionally, it has a distance window and a 9-bladed, rounded aperture for ultra smooth bokeh.
As for focus, AF is via Sigma's Hyspersonic Motor (HSM) technology, which results in fast, virtually silent AF. Additionally, features full time manual focus capability. SLR Gear reports AF as being very accurate, too.
Overall conclusion: praise at the highest level, with SLR Gear reviewers even going so far as to say that this Sigma is probably the most exciting lens they will test all year (and it's only the start of April.
Unfortunately, pricing is still TBA here.
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