Standard zoom lens series pentax smc da lens mounts pentax k pentax kaf3 lens speed 4 focal length 17 70 mm zoom factor 41 times suitable for sensor type aps c construction zoom lens area of use landscape photography close up photography focus internal focus auto focus manual focus af motor ultrasonic motor usm reduced frame size max magnification 13 2 closest focusing distance 28 cm focal length equivalent to 35mm camera 26 107 mm lens typ