Camera attached to helicopter rotor

[CMW403]

http://www.youtube.com/watch?v=EnrwrwMfNSs

"When the frame rate approaches an integer multiple of the rotation rate the horizon becomes a sinusoid that appears to have an amplitude that's a function of the rotor's change in attack angle over the course of one rotation "

Very cool.

[SJW]

So cool to see the change in wave length.

[Mar]

The alternating ground/sky is caused by a tilt in the blades.

[J-hop]

Signal aliasing 101