Versatile Ultra-Wide Prime. The Sigma 17mm f/4 DG DN Contemporary’s build is compact and ultra-light. It weighs just under 0.5 lb. and takes 55mm filters. Its focal length, constant f/4 maximum aperture, and rounded seven-blade diaphragm make it great for vlogging, landscape photography, nature photography, and much more. Using an APS-C camera? You’ll get a 25.5mm equivalent focal length.

High-Quality Optical Design. As a part of Sigma’s Contemporary lens line, the 17mm f/4 goes through rigorous testing to ensure high image quality. Its eight-group/nine-element optical design features one Special Low-Dispersion element and three aspherical elements that correct for chromatic aberrations and color fringing while ensuring high image sharpness, clarity, and contrast. A Super Multi-Layer coating minimizes lens flare and ghosting, helping to provide high contrast even in strong lighting.

Fast, Quiet Autofocus System. The 17mm’s integrated stepping autofocus motor provides fast, quiet operation in a broad range of shooting situations, and its optimized AF algorithm helps facilitate smooth performance. You get a 4.7-inch minimum focusing distance with a 1:3.6 maximum magnification ratio, letting you take macro-style close-up shots.