This is only some kind of shy remark to two outstanding demonstrations on the “rolling shutter effect”:
Because I am referring to two sources I decided to write this as an extra post.
In the last sentence of Eriks post he expressed his hope that this might be an inspiration to others - and it was!
I wanted to see this in a more mathematical way. My simple idea is to use complex numbers - in particular its phase - for demonstration. This means I just plot complex 'z'; a multiplication with means a rotation of the whole complex plane. The idea is now to make this rotation dependent on the imaginary part (i.e. scanning along a horizontal line). Mathematica brings everything needed - I end up with a simple one-liner:
exp(φ)
In[]:=
Manipulate[ComplexPlot[Exp[I(vIm[z]+ϕ)]z,{z,-2-2I,2+2I},ColorFunction->"CyclicArg",ImageSize->Large,PerformanceGoal->"Quality"],{{v,0,"RotationSpeed"},-2,2},{{ϕ,0,"PhaseShift"},-1,1}]
Out[]=
ADDENDUM: I need to emphasize that this does by no means compare with the mentioned posts above: it is not suitable as a descriptive demo for explanation - just an attempt for a mathematical formulation.