Standard lens series pentax smc da lens mounts pentax k pentax kaf3 lens speed 14 focal length 55 mm suitable for sensor type aps c construction prime lens area of use night photography astrophotography portrait photography indoor photography action photography focus auto focus manual focus af motor ultrasonic motor usm reduced frame size max magnification 15 8 closest focusing distance 45 cm focal length equivalent to 35mm camera 80 mm lens typ