I was looking at Arcturus with a pair of binoculars, and noticed that when they vibrate due to my heartbeat, Arcturus seemed to move differently than the other dimmer stars.

I started playing with that visual effect and noticed that it happens both vertically and horizontally, and that I could even make it "overlap" with a nearby star. It is like it either lags or is ahead of the others in terms of how it moves in the field of view as the binoculars do their slight shake. Why is that?

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    $\begingroup$ At first guess, I'd go with Persistence of vision en.wikipedia.org/wiki/Persistence_of_vision on the brighter star as compared to the dimmer ones. $\endgroup$ Jun 22 '15 at 13:49
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    $\begingroup$ With binocs, I've always noticed brighter stars seem to form persistent trails and tend to move in a "delayed" manner, while fainter stars don't seem to move that way. (Although sometimes the fainter ones vanish completely until the binocs are steady again.) I agree it's probably down to the persistence of vision effect. Can't comment on exactly how/why it happens though... $\endgroup$
    – Andy
    Jun 22 '15 at 14:40

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