Fast f/1.8 Aperture Telephoto. The Sigma 135mm f/1.8 DG HSM Art for L-mount’s bright f/1.8 maximum aperture and rounded, nine-blade diaphragm combine to provide shallow depth of field, smooth bokeh, and selective focusing, making this lens ideal for portraiture, low-light shooting, and other artistic applications. You can also use this lens on APS-C models, on which it’ll provide a 202.5mm equivalent focal length.

High-Quality Optics. As a part of Sigma’s Art lens line, the 135mm f/1.8 goes through rigorous testing to ensure high image quality. Two “F” Low-Dispersion elements and two Super Low-Dispersion glass elements correct for chromatic aberrations and color fringing while ensuring high image sharpness, clarity, and contrast. The Super Multi-Layer Coating minimizes lens flare and ghosting, helping to provide high contrast, even in strong lighting.

Hyper Sonic Motor Autofocus System. The autofocus system provides fast, smooth, and quiet operation in a broad range of shooting situations. You can also manually override the autofocus motor at any time by rotating the focusing ring, giving you quick fine-tuning ability.