The SIGMA 20mm F1.4 DG DN | Art delivers exceptionally detailed results that easily satisfy the high demands of professional photography and other high-end applications. With 17 glass elements arranged in 15 groups, including two SLD, three aspherical glass elements and the largest class double-sided aspherical glass element in SIGMA’s history, the 20mm F1.4 DG DN | Art rigorously suppresses various optical aberrations such as sagittal coma flare or image distortion to produce highly-detailed images with exceptional sharpness and accuracy from the center to the furthest corners, allowing photographers to make use of the entire field of view afforded by its ultra-wide viewing angle. This ultimate astrophotography lens is the culmination of the unparalleled manufacturing technology of SIGMA’s sole production base in Aizu, Japan, as well as the company’s know-how and experience with large-aperture wide-angle lenses, such as the SIGMA 20mm F1.4 DG HSM | Art, the SIGMA 14mm F1.8 DG HSM | Art and the SIGMA 14-24mm F2.8 DG DN | Art.