This Sigma 150-500mm f/5-6.3 DG OS HSM APO Lens for Pentax is for digital SLR cameras with a Pentax K lens mount. It is an ultra telephoto zoom lens ideal for nature, wildlife, or sports photography. This zoom range translates into an equivalent range of 225-750mm when used with digital SLR cameras with an APS size chip. The lens is also compatible with full frame cameras.

The HSM (Hyper Sonic Motor), APO apochromatic design, three elements of SLD (Special Low Dispersion) glass, and multicoated optics all enable this lens to provide a high level of performance throughout its entire zoom range, as well as versatility. A rear focus system insures quick, convenient manual focus and a non-rotating front barrel.

The improved DG lens design corrects for various aberrations. This lens is specially coated to get the best color balance, while cutting down on ghosting caused by reflections from the digital image sensor. The lens provides the utmost correction against lateral chromatic aberration, which is a serious problem for digital SLR cameras.