Part of the Sigmas Contemporary line, this Sigma 28-70mm f/2.8 DG DN OS Contemporary Lens is a versatile zoom designed for Leica L-mount full-frame mirrorless systems to achieve a balance between impressive optical performance and convenience. As a wide-angle to portrait length with a 28-70mm focal length range, it can also be used with APS-C models where it provides a 42-105mm equivalent focal length range. For improved clarity and accurate colour, the 16-elements-in-12-groups optical design includes two F Low Dispersion (FLD) elements and two Special Low Dispersion (SLD) elements to notably reduce chromatic abberations and colour fringing. Three aspherical elements are incorporated to control spherical aberrations and distortion. With only one lightweight focusing element, the autofocusing unit is kept small, which contributes to the lens more compact and lighter build than similar lenses. Additionally, the elements receive both Super Multi-Layer and Nano Porous coatings for minimising lens flare and ghosting to produce contrast-rich and colour-neutral imagery.The optical attributes are complemented by an integrated stepping AF motor, which achieves quick, quiet, and accurate autofocus performance, and an optimised AF algorithm, which aids in producing a smoother focusing. The mount is rubber sealed to render it dust-and splash-resistant for operation in inclement weather, and mounting accuracy as well as rigidity are improved thanks to the brass construction of the bayonet. A rounded 9-blade diaphragm contributes to a pleasing boken quality. This versatile lens comes with front and rear lens caps, a lens hood and a lens case.
