How does wireless ETTL work?
I was thinking of picking up the speedlite 600ex-rt and the wireless remote as well. I generally understand how ettl works when on top of the camera, but how does it how much light to output if it doesn't know how far away it is from the subject? How would the camera know if the flash is 1 foot vs 5 ft away cause that would require different flash out puts.
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from Abstract Architecture
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