Versatile Wide-Angle Prime. The Sigma 20mm f/2 DG DN Contemporary’s compact build and versatile focal length make it ideal for a broad range of shooting situations, including landscapes, cityscapes, handheld vlogging, and video streaming. The bright f/2 aperture is great for astrophotography and night-sky photography, in addition to letting you shoot in low light and offering excellent focus control when using shallow depth-of-field techniques. The rounded nine-blade diaphragm lets you render smooth bokeh. Using an APS-C camera? You’ll get a focal length equivalent to 30mm.

Stepping Autofocus Motor. The stepping motor provides fast, smooth, and nearly silent autofocus operation for stills and video alike. The lens’s internal-focusing design gives you maximum responsiveness, and you also get full-time manual-focus override for even greater precision.

Advanced Optics. This lens’s eleven-group/thirteen-element optical design includes one Special Low-Dispersion element, three aspherical elements, and one “F” Low-Dispersion element, which work together to minimize spherical aberrations and fringing while improving clarity, sharpness, and color accuracy. A Super Multi-Layer Coating has been applied to each element to boost contrast, and to combat ghosting and flare.

High-Quality Build. The Sigma 20mm’s Thermally Stable Composite build is dust- and splash-resistant, so that you can use it in adverse conditions. It also boasts a brass bayonet mount for maximum durability.