Originally posted by OJGoreng I meant performance-wise. The loss of a stop of light will decrease AF speed and accuracy somewhat. In the past week we've had both very bright and heavily overcast days, and the difference in AF performance under those different circumstances is really noticeable.
So the limitation of the dslr AF system at f8, which is to be expected. I am aware of this, and have considered getting the Nikon Z7 instead, because I don't so much mind the loss of AF speed in lesser light, but would mind the loss in accuracy. Mirrorless AF enables high accuracy at smaller apertures, like the Sony A9 with dead on AF at f11. Have you tried the Z7 with your lens?
Is it AF-C that you are referring to, or also loss of accuracy in AF-S?
Regardless though, the DA560 is unreliable on the K3 at f5.6 in anything but high contrast, bright daylight, especially with first focus acquisition, so it is not all the physical limitations of the dslr AF system.
I have seen pin sharp images from D500 with 500PF and 1.4tc of birds under canopy, so with care I expect it to be possible.
Chris