[mattdm]

So, here's an interesting thing about P-TTL and P mode on the K10D with a flash mounted. This is with the Metz 48 AF-1, but I assume it's with any flash — it'd be interesting to have confirmation.

At ISO 320 or below, it tends to pick things like shutter speed 1/60th and f/2.8 or f/3.5. (This is a f/2.8 max lens, in MTF P mode — I should test the other P options too.) But at ISO 400, there's a sudden jump to preferring f/8 (same shutter speeds).

It makes sense, of course, that higher ISOs allow smaller apertures, but the interesting thing is that there's a clear jump in behavior right at that point — the 1/3 stop increase in ISO causes a 2 1/3 stop decrease in aperture.

(Either way, the flash power is adjusted to the right exposure.)