What can you see? Most people will have seen the wagon wheel effect in films of horse-drawn vehicles (western films are often cited as examples) or other vehicles with spoked wheels. When driving fast, it can be seen that, contrary to expectations, the spoked wheels do not turn forwards, but rather stand still or even seem to turn backwards. To understand the effect, we have to do a little math.

For example, if a wheel with 6 spokes is filmed at 24 frames per second (fps) (this fps rate is standard today), then we get a still image exactly when the wheel rotates 60 degrees in 1 24th of a second. The 60 degrees result from the quotient 360 degrees through 6 spokes. This also means that the wheel moves slightly backwards at 59 degrees and forwards slightly at 61 degrees.

What can you do? After the program wagon wheel has started (with type: 1 – 2 – 3 = 1), the angle per second (aps_1) can be changed for a wheel with 6 spokes (for one rotation per second, aps_1 is 360 degrees). The speed is adjusted with the aps_1 slider (0 ≤ aps_1 ≤ 4500). A fine adjustment in steps of 5 can be made with the right/left buttons. At fps = 24 the result is a still image at aps_1 = 1440 ((360/6) * 24). The resolution is adjusted either with the fps slider (1 ≤ fps ≤ 100) or in steps of 1with the l/h buttons (l = lower, h = higher resolution). Which aps_1 result in still images at other fps (e.g. 100)?

With type: 1 – 2 – 3 = 2 you can superimpose a second wheel and control its rotation speed separately with aps_2 (0 ≤ aps_2 ≤ 4500). The fine adjustment in steps of 5 can be made with the up/down buttons.With which values can you achieve that the movements of the wheels appear in opposite directions?

With type: 1 – 2 – 3 = 3 you can display nine wheels with 2 to 10 spokes in parallel. You can control their rotation speed with aps_n. This allows you to compare the effect for the different number of spokes. The speed is adjusted with the aps_n slider (0 ≤ aps_n ≤ 5500). The fine adjustment in steps of 5 can be made with the +/- buttons. At what values of aps_n do multiple wheels simultaneously show still images?
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Related topics: Color Wagon Wheel, Duchamps Rotoreliefs, flicker colors