Tested the AF360FGZ and a Metz 50 AF-1 quite thoroughly (at a shop) with 3 different original Pentax prime lenses of mine and compare the results against the built-in flash head-to-head, I saw the results are mostly pathetic!
So, this P of the P-TTL stands for Pathetic as regularly told by different Pentaxians is really true! I hate much for the fact that the on-board P-TTL flash of both my K-r and K-x used to be more accurate than my new flagship K-5! >:-o
So, what has happened actually? That is the infamous K-5 overexposure problem! Mind you that my K-5 has already had the latest firmware of version 1.12 programmed! And that overexposure error is in a great amount, so that many parts of the pictures are burnt! :-( And, that happened even with the flash fired on a white board (which should normally cause underexposure for typical flash exposure behaviour!)! Damn!!
The strangest thing is that the Metz overexposes even more, I guess it is typically in about 1EV for all those direct flash (not even to talk about bounce!), the 360 is by about a half stop more at +0.5EV in general. The on-board flash typically is correct for ISO 100 and 200 with DA lenses, but not at higher ISO 400 or above nor with Pentax original A/F/FA lenses of the previous generations, either any of which will cause more overexposure as a result! Again, my K-r and K-x does not exhibit these problems!!
So, what happens with Pentax and the K-5? Is the Pentax flash system is really so Pathetic nowadays, especially that one adopted in the still-the-current "flagship" K-5?! >:-{
Read Also:-
P-TTL Reliability
Re-published: How (Auto) Flashes and P-TTL Work?
My K-5 Impressions after the First 1,000+ Shots (Somewhat Detailed)
Who Said K-5 Cannot be Used as a JPEG Camera?
Ten Things that I Want Ricoh to Do for Pentax