
This ultra wide angle zoom lens incorporates the latest optical design & provides superior performance. FLD (“F” Low Dispersion) glass elements, which have performance equal to fluorite, & SLD (Special Low Dispersion) glass elements provide excellent correction of colour aberration. Aspherical lenses give advanced performance with a compact & lightweight construction & ensure high image quality throughout the entire zoom range. The Super Multi-Layer Coating reduces flare & ghosting & incorporation of HSM ensures quiet & high speed autofocus as well as full-time manual focus capability. This lens has superior peripheral brightness & provides sharp & high contrast images even at the maximum apertures. Full frame ultra wide angle zoom lens Sigma designed & produced the first wide-angle zoom lens, the “zoom gamma 21-35mm F3.5-4”, in 1979. Sigma has since introduced a number of wide angle zoom lenses. The SIGMA 12-24mm F4.5-5.6 II DG HSM is the successor of the SIGMA 12-24mm F4.5-5.6 EX DG ASPHERICAL / HSM which was launched in November 2003. This ultra wide angle zoom lens is ideal for digital SLRs with a 35mm full frame image sensor & incorporates the latest optical design. Superior image quality Four FLD (“F” Low Dispersion) glass elements, which have performance equal to fluorite, & one SLD (Special Low Dispersion) glass element provide excellent correction of colour aberration. Three glass mold elements & one hybrid aspherical compensate for all types of aberration & ensure high optical performance. *FLD glass is the highest level low dispersion glass available with extremely high light transmission. This optical glass has a performance equal to fluorite glass which has a low refractive index & low dispersion compared to current optical glass. It also benefits from high anomalous dispersion. These characteristics give excellent correction for residual chromatic aberration (secondary spectrum) which cannot be corrected by ordinary optical glass & ensures high definition & high contrast images. Super Multi-Layer Coating Sigma’s Super Multi-Layer Coating reduces flare & ghosting which could otherwise create problems when extraneous light hits the lens’ front element. It also provides sharp & high contrast images throughout the entire zoom range. Superior peripheral brightness The design of front lens group minimizes light fall off & increases peripheral brightness. Exaggerated perspective The wide-angle of view produces striking images with exaggerated perspective, enabling photographers to emphasize the subject. Compact construction Incorporation of four aspherical lenses provides a compact construction with a diameter of 85mm, overall length of 120.2mm & weight of 670g. The compact construction makes this lens ideal for travel photography. Quiet & high speed autofocus Incorporation of HSM (Hyper Sonic Motor) ensures quiet & high speed autofocus, while allowing full-time manual focus override. Inner focusing system This lens incorporates an inner focusing system, which eliminates front lens rotation which also minimises fluctuation of aberration caused by the focusing system. Petal-type hood This lens is equipped with a built-in petal-type hood to block out extraneous light & reduce internal reflections.