Where Has All the Motion Gone?

Click on the big button to toggle between a blurred version of the display and an unblurred version. When the display is blurred, the motion is dramatic; when the display is not blurred, there is only minimal motion. The effect can also be seen with a defocused lens. Blur eliminates high-spatial frequencies. It does not add information to the image. Why, therefore, does the removal of high-spatial frequencies add motion to the display? The buttons and levers allow control over the many of the parameters in the display.

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