PENTAX DA 10-17mm f/3.5-4.5 ED (IF) Fish-Eye Lens for Pentax Digital SLR 10-17mm fisheye lens with f/3.5-4.5 maximum aperture for Pentax digital SLR cameras Creates images with expanded perspective, with creatively deformed outlook and sharp pan focus Image circle is designed to perfectly match 23.5 x 15.7mm CCD used in Pentax digital SLRs Water- and oil-repellant SP lens coatings; extra-low-dispersion glass for superior sharpness Minimum focusing distance of 0.46 feet; measures 2.8 inches in diameter; weighs 11.3 ounces