BBC publishes an article "Why is it so hard to swat a fly?" comparing human vision with fly vision:
"...have a look at a clock with a ticking hand. As a human, you see the clock ticking at a particular speed. But for a turtle it would appear to be ticking at twice that speed. For most fly species, each tick would drag by about four times more slowly. In effect, the speed of time differs depending on your species.
This happens because animals see the world around them like a continuous video. But in reality, they piece together images sent from the eyes to the brain in distinct flashes a set number of times per second. Humans average 60 flashes per second, turtles 15, and flies 250."
Interesting article. I suppose the statement "Humans average 60 flashes per second" really means each cone is on average activated 60 times/sec. Since the cone activated can be from an arbitrary location in retina, what's received by the brain would probably be a series of randomly sub-sampled images. Suppose the brain interpolates the missing "pixels" to create a full frame, then it appears me to the flies see more "clearly", rather than faster, than human.
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