1. High image quality The two lenses are the newest members of the exclusive DA Star series, developed as part of PENTAX's pursuit of the highest image quality, and are designed to deliver the top optical performance of all PENTAX interchangeable lenses. Combining a host of advanced technologies including super-low-dispersion optical elements, extra-low dispersion (ED) optical elements and PENTAX-original lens coatings, they assure outstanding image description with clear, high-contrast images, even at edges of the image field. 2. Dust/water-resistant construction Featuring a set of special seals, the lenses feature a reliable dust-resistant, water-resistant construction to prevent intrusion of dust, water and moisture into the lens body. 3. Quick-Shift Focus system The PENTAX-invented Quick-Shift Focus system allows instant switching to manual-focus operation, after the subject is captured in focus by the camera's autofocus system. 4. SP coating to block dust and stains The front surface of the optics is treated with the PENTAX-original Super Protect (SP) coating. Applying a special fluorine compound to the lens surface through a vapor deposition process, this coating effectively repels dust, water and grease, making it easy to wipe off annoying stains such as fingerprints and cosmetic marks. 5. Digital SLR-exclusive optical design Thanks to a combination of special lens coatings, ideal curvature and best positioning of optical elements, these lenses are designed to optimize digital imaging characteristics, while effectively minimizing flare and ghost images. Their image circle is perfectly proportioned to the image-sensor size of PENTAX digital SLR cameras. Despite their large maximum aperture, they are designed to be compact and lightweight to enhance maneuverability and operability. [Main Features of the smc PENTAX-DA60-250mmF4ED[IF] SDM Lens] 1. When mounted on a PENTAX digital SLR camera body, this zoom lens provides focal lengths from 92mm to 383mm in the 35mm format. Its 4.2-times zoom ratio covers a broad telephoto range, making it ideal for capturing various sports scenes and portraits. 2. Two extra-low dispersion (ED) optical elements are incorporated into the optics for minimal chromatic aberrations. A unique nonlinear shifting system employed in the zoom mechanism effectively reduces field curvature aberrations and assures solid image-description performance at all focal lengths. 3. The large F4 maximum aperture is retained over the entire zoom range to assure a faster shutter speed or reduce the depth of field. 4. An innovative hybrid AF system offers both extra-smooth, super-quiet SDM autofocus operation using a supersonic motor installed in the lens body and conventional autofocus operation using a motor built into the camera body. Specifications Lens Mount: PENTAX KAF2 mount Lens Construction: 15 elements in 13 groups Angle of View: 26.5 - 6.5 degrees Aperture: F4 Number of Diaphragm Blades: 9 Minimum Aperture: F32 Minimum Focusing Distance: 43.2 inches Filter Diameter: 67mm Maximum Magnification: 0.15X Dimensions: 3.2 x 6.6" Weight: 36.7 oz. (w/o hood), 39.5 oz. (w/hood), 43.4 oz. (w/hood & tripod mount) Case: S100-200 Objective Cap: O-LC67 Hood: PH-RBK 67mm Lens Aperture Ring: N/A Tripod Adapter: Yes Diaphragm Control: Fully Automatic Focal Length: 60-250mm (equiv. 90-375mm) Notes: Supersonic motor, Quick-shift focus, SP (Super Protect) coating, Filter window, Detachable tripod mount