I have some info for any one interested in compatibility of the KENKO 1.5X AF Tele-converter. I purchased the converter to mate up with a Pentax 50-135mm DA* f2.8 lens on a K10D digital. The auto focus does not work and the menus don't function properly. I did limited testing because I did not want to damage it. The converter seemed to function properly, but hunted around a lot when focusing with a DA 50-200mm lens. Kenko does say this would happen with slow lenses and recommends manual focusing. I’m still looking for a converter for this set-up if any one has info please feel free to join in.
Joe D.