K10D

I am using a Sigma EF-500 DG Super with the camera set to the P position. I only get a correct picture every now and again all the rest are very under exposed this problem does not occour on a istDS, with exactly the same settings. The problem also seems to go away when the flash head is pointing up any ideas?

Hi Gordon

IIRC the early Sigma EF-500 DG Super's had to go back to Sigma to be re-chipped. The K10D does not support TTL it only supports P-TTL, A or Manual, the *isD supports TTL.

Was it bought new or SH?

I had a look at the Sigma compatability list for the EF-500 DG Super with Pentax bodies and the K10D isn't mentioned although other P-TTL Pentax bodies are.