Pentax ISTDS Operation Manual - Page 180

178 Lens names and mount names FA prime lenses (non-zoom lenses) and DA, D FA, FA J and F lenses use the KAF mount. Of the FA zoom lenses, power zoom enabled lenses use the KAF2 mount. Lenses without power zoom use the KAF mount. See the lens manual for details. This camera does not have a power zoom function. Lenses and accessories that cannot be used with this camera When aperture ring is set at other than s (Auto) or a lens without a s (Auto) position or accessories such as an auto extension tube or auto bellows are used, camera does not operate unless [Using aperture ring] is set to [2 (Permitted)] in the [A Custom] menu (p.101). Refer to Notes on [Using Aperture Ring] (p.179) for restriction that apply when [Using aperture ring] is set to [2 (Permitted)] in the [A Custom] menu. All camera exposure modes are available when using DA/FA J or lenses with Aperture s (Auto) position set to that position. Lens and Built-in Flash The built-in flash cannot be regulated and fully fires when pre A lenses or 6 soft lenses are used. Note that the built-in flash cannot be used as the Auto Flash. Appendix