A truly long-reaching telephoto zoom for Pentax DSLRs, the HD PENTAX D FA 150-450mm f/4.5-5.6 DC AW Lens pairs advanced optical and mechanical design elements with an extensive 225-675mm-equivalent focal length range when used on APS-C cameras. Extra-low dispersion glass elements are incorporated within the construction to minimize chromatic aberrations and distortions, as well as produce a high degree of sharpness throughout the zoom range. HD coatings have also been applied to lens elements to reduce reflections and flare and a Super Protect coating also helps to shield the front and rear elements from dust, water, and oils. In regard to focusing, a DC autofocus motor realizes fast and quiet performance and is accentuated by the Quick-Shift Focus System for changing between AF and MF control by simply turning the focusing ring. Designed for wildlife, nature, and sports shooters, this long lens pairs sophisticated optical traits with fast-paced focusing controls for intuitive handling.Further complementing the focusing system is the inclusion of both focus preset and focus range limiter settings for faster handling. Additionally, benefitting its use in trying conditions, the lens features a weather-resistant construction, with 21 integrated seals, to prevent dust and moisture from entering the lens.