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No zig-zags, only sine waves, honest ...
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No zig-zags, only sine waves, honest ...
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RD
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No zig-zags, only sine waves, honest ...
«
on:
14/12/2017 09:17:28 »
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5703117/
«
Last Edit: 14/12/2017 09:21:39 by
RD
»
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chris
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Re: No zig-zags, only sine waves, honest ...
«
Reply #1 on:
14/12/2017 19:48:56 »
Now that is really strange!
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Re: No zig-zags, only sine waves, honest ...
«
Reply #2 on:
15/12/2017 09:49:07 »
You can see why if you look at the Taylor series for a sine/cosine curve.
When you focus on the peaks of the sine wave, it is basically a parabola. For small x, it has an equation like:
cos(x) = 1 - x
2
/2! + O(x
4
)
When you focus on the line
joining
the peaks and troughs, it is basically a straight line. For small x, it has an equation like:
sin(x) = x - O(x
3
)
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RD
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Re: No zig-zags, only sine waves, honest ...
«
Reply #3 on:
15/12/2017 11:01:57 »
There's no variation in tone within each side of what appear to be zig-zags
.
That would occur if they were highlight & shadow regions on straight-cuts,
but not if they were scalloped edges, then there would be graduations of tone within shadow & highlights.
Brain says : If it's uniformly lit (bright or dark) it has to be a straight edge, (even when it's a curve).
«
Last Edit: 15/12/2017 11:12:16 by
RD
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curvature blindness
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optical illusion
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kohske takahashi
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