Last week, a curious video emerged on YouTube, appearing to show a helicopter “floating” elegantly above Hong Kong’s Victoria Harbour.
Filmmaker Chris Fay created the illusion after syncing his camera’s frame rate with the rotation speed of the helicopter’s blades to precision.
In other words, if the helicopter blades were spinning at a total of 24 revolutions per second, and Fay’s camera also captured 24 still image frames per second, each of the frames would show the blades in the exact same position.
