Standard zoom lens series pentax da lens mount pentax kaf3 lens speed 4 focal length 20 40 mm zoom factor 2 times suitable for sensor type aps c construction zoom lens area of use portrait photography landscape photography close up photography focus manual focus internal focus auto focus af motor no internal af motor circular aperture closest focusing distance 28 cm focal length equivalent to 35mm camera 30 5 61 5 mm lens type ed lens construction