I recently purchased a Z-1 I have used two Sigma lens on it The camrea sometimes decides these lenses are f1.2 (24-70 f3.5-5.6/28-90 f3.5-5.6)and wont focus. I have also used Pentax current 50mm f1.4 and an old Pentax F 28-80 with no problems.
Do I have a compatibility problem or a camera problem regards Paul