Marc Alhadeff posted the review of the new Sigma 14mm F/1.8 DG HSM Art lens:
The Sigma 14mm F1.8 DG HSM Art (1600 euros) is an excellent lens optically for a wide angle with the fastest aperture available for that focal length.
Centre sharpness is excellent , and corners are already good wide open and become progressively excellent
The Sigma 14mm F1.8 is certainly the best 14mm available in the market in term of sharpness , bokeh and color rendition, and it low coma makes it suited for astrophotography
The F1.8 allows for some unique effect of background blur for a wide angle that has no equivalent
The only issue is the capricious Autofocus and the price tag (1600 euros), one of the most expensive of the Art line