Sep 13, 2015
P-TTL Test Images
Introduction
In support of user mcgregni's Pentax flash guide PF staff has run a number of tests of the P-TTL functionality. Specifically we were tasked with investigating the consistency of P-TTL in various conditions as well of investigating whether or not FA-, F-, and A-series lenses perform identically.
We used the comparable lenses, namely the 50mm F1.4 from the FA-, F- and A- series.
We found that the FA and F lenses perform about the same with a tendency towards underexposure, whereas the A-series lens tended towards overexposure (which can all be corrected through EV compensation). The A-series lens is fully compatible with P-TTL.
Read on for the details and sample photos.