A question frequently asked is how good is the auto focus of the Canon EOS R6? Especially when paired with a small aperture lens like the f11. Combine the small aperture with super telephoto focal length of 800mm. It would mean the auto focus algorithm has to be pretty good. By that I mean the speed with which it acquires the initial focus, and then how good it is at sticking and tracking the subject. I recently put this to test by attempting to capture swallows in flight.  Swallows are small birds. They fly fast. They do not seem to have a fixed pattern and turn and swoop and dive and ascend with their beaks open to swallow flying insects.   I was pleasantly surprised the Canon EOS R6 did very well. The Canon EOS R6 with the RF 800mm f11 acquired the auto focus quickly. More important the auto focus was accurate. And then stuck to the subject like glue. The subject tracking was accurate and kept the bird in flight. didn't matter whether the swallow was flying towards me, diving do