Fast f/1.4 Aperture Normal-Range Prime. The Sigma 40mm f/1.4 DG HSM Art for L-mount’s fast f/1.4 aperture enables great low-light performance, wide-angle images, and shallow depth of field. The 40mm perspective is popular for street photography, full-length portraits, and outdoor architectural shots. Using a APS-C format camera? You’ll have a focal length equivalent to 60mm.

High-Quality Optics. As a part of Sigma’s Art lens line, this lens goes through Sigma’s rigorous A1 testing to ensure high image quality. One aspherical element helps to eliminate sagittal coma flare, distortion, and axial chromatic aberration, while three “F” Low-Dispersion elements work in unison to correct for chromatic aberrations throughout the entire focusing range while ensuring high image sharpness, clarity, and contrast. The Super Multi-Layer Coating minimizes lens flare and ghosting, helping to provide high color accuracy.

Hyper Sonic Motor Autofocus System. Provides fast, smooth, and quiet operation in a wide variety 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.