DxOMark published their Sigma 12-24mm f/4 DG HSM Art Lens (Canon) review and test results. Tested on Canon EOS 5D Mark IV, Sigma 12-24mm f/4 DG HSM Art Lens achieved an overall DxOMark score of 23 points, with a combination of 16 P-Mpix Sharpness, 4.7 TStop Transmission, 0.3% Distortion, -0.7 EV Vignetting and 8μm Chr.aberration.
There are two obvious lenses that are directly comparable to this new Sigma 12-24mm f/4 DG HSM Art Lens ($1,599): Canon EF 11-24mm f/4L USM lens ($2,799) and Sigma 12-24mm F/4.5-5.6 EG DG HSM II Lens ($949).
“As an Art lens, the new Sigma comfortably outperforms the older Sigma lens in every measurement category, offering increased sharpness and light transmission, and decreased distortion, vignetting, and chromatic aberration.”
“Up against the Canon, the Sigma performs remarkably well. While it misses out fractionally on the overall DxOMark score (23 vs. 25), and while the spread of performance is greater throughout the range compared to the more uniform Canon, the Sigma exhibits lower distortion, lower vignetting, and much-reduced chromatic aberration.”
Conclusion from DxOMark:
Overall, this is a very strong showing for Sigma. Yes, it is outperformed by the Canon lens for overall score, but given that the cost of the Canon is almost double, for many users, the Sigma will be just as good. While Canon will point to its hand-ground aspherical lenses as a key factor and the reason for the difference in cost, given that the performance is so similar, it seems Sigma’s molded aspherical elements are almost a match… and let you keep a big chunk of money in your pocket. Of course, choice is personal. If you’re looking for an ultra-wide lens, both the Canon and Sigma Art will offer great performance in this range, but in terms of value for money, the Sigma 12-24mm f/4 DG HSM Art wins hands down.
You can read the full review at DxOMark.