Sigma 12-24mm f/4-5.6 II DG HSM £530, $950
delivers an eye-popping viewing angle
You could be forgiven for thinking that this is a DXformat lens, considering its minimum focal length. In fact, it’s an FX lens that delivers an astonishing maximum viewing angle of 122 degrees, leaving the Nikon 14-24mm and Tamron 15-30mm in its wake. The built-in lens hood precludes the use of screw-in filters, but at least the two-part hood enables the use of 82mm filters at the long end of the zoom range.
Top-quality glass includes four FLD (Fluorite-grade Low Dispersion) elements, one SLD (Special Low Dispersion) and four aspherical elements. Build quality also feels impressive.
Performance
The ring-type ultrasonic autofocus system is fast and quiet, while sharpness and contrast are very nearly as impressive as from the Nikon 14-24mm lens. The Sigma does extremely well to maintain edge sharpness, considering its incredibly wide viewing angle. To get the same viewing angles on your DX camera, the Sigma 8-16mm is essentially the same lens in APS-C format.