The "halo cloud" was just an optical illusion caused by sunlight hitting a cloud at just the right Angle.

“光环云”是由阳光以恰到好处的角度触及云层而引起的一种光学错觉。

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The 720 Angle turning and two people hovering in the air have never been done in the illusion performing history.

水上悬人的720度空中旋转和双人腾空在魔术表演史上是首次实现。

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When we see a sharp Angle, our mind tries to adjust it to a right angel. In this optical illusion, the straight, red lines are pushed out and look rounded.

当我们看到锐角的时候，我们的视觉神经会无意识的把它看成是直角，所以在这张图里面，垂直的红线就在这种机制的作用下被撑的看起来有了弧度。

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Since human depth perception relies on calculating the difference between the angle of view coming to each eye, the result is a 3-D optical illusion.

FORBES: Adventures in the Third Dimension