Pentax 21497 DA 18-270mm f/3.5-6.3 ED SDM Lens: * 18-270mm zoom lens offers a 15x zoom ratio covering focal lengths from 27.5mm wide angle to 414mm super telephoto in the 25mm format * 2 extra-low dispersion elements * Rounded diaphragm blades produces beautiful photos while minimizing streaking effect of point light sources * Pentax-original SDM autofocus system offers exceptionally smooth and quiet autofocus operation * Focus mode automatically switches to SDM-assisted auto-focusing when mounted on an SDM compatible Pentax K-mount digital camera body