Covering a useful variety of ultra-wide focal lengths, the Sigma 12-24mm f/4 DG HSM is an Art-series zoom, characterized by its advanced design to greatly reduce distortion for a high degree of sharpness. A series of low dispersion and aspherical elements minimize both chromatic and spherical aberrations throughout the zoom range in order to achieve high clarity and color accuracy. A Super Multi-Layer Coating also helps to suppress lens flare and ghosting for color-accurate, contrast-rich imagery in a variety of lighting conditions.