DA 17-70mm F4 AL (IF) SDM - Overview
This lens is an indispensable tool for ambitious photographers. With an equivalent focal length of 26-107mm (in 35mm film format) it offers the crucial benefit of additional range when normal "standard" zooms generally extend to 82mm equivalent. Not only the focal length range is remarkable: with the KAF3 lens mount it relinquishes the classical mechanical autofocus drive for the first time in favour of faster and quieter ultrasonic technology. The lens construction: 17 elements in 12 groups, including 2 aspherical lens elements - guarantees of outstanding pictures. Important details, such as fixed aperture throughout the zoom range also provide excellent control.
Smc DA 17-70mm's lens mount is KAF3-type, which means that with K100D, *ist D, *ist DS, and *ist DL, the focus can only be performed manually.