Sometimes, when I look at one of the rosettes, one or two others in my peripheral vision appear to rotate.
@AkiyoshiKitaoka @_Kcnarf
#rhombus #rhombusworms #opticalillusionspic.twitter.com/1rZoyrZVKG
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With this one, I can see rotation pretty easily (clockwise for the one on the left, and counter-clockwise for the one on the right), but for the one with the black background, it seems to be more dependent on my eyes being in motion...
...but I am not entirely sure...I may not be getting consistent results. It seems possible that the effect is varying depending on what image I had been staring at beforehand...looking from one to the other may be affecting how I perceive the second one. 
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