If the photocells don't respond fast enough, I wonder if using a photodiode, prebiased with a little bit of voltage, connected to an A/D input, continuously sampled would respond fast.
It would be neat if I could get pictures like that, but I live in a bit of a valley with trees all around. Not much of a horizontal view unless I get up about 100ft...at least I get deer walking thru the yard every morning and evening.
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