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Carpal Tunnel
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Carpal Tunnel
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Good point. I think you've got it.
Now let's turn it from a word post into a Word post: sounds like Greek - what does "strobos" mean, anyway?
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Carpal Tunnel
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Carpal Tunnel
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e American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
stroboscope
SYLLABICATION:
stro·bo·scope
PRONUNCIATION:
strb-skp
NOUN:
Any of various instruments used to observe moving objects by making them
appear stationary, especially with pulsed illumination or mechanical devices that
intermittently interrupt observation.
ETYMOLOGY:
Greek strobos, a whirling; see streb(h)- in Appendix I + –scope.
OTHER FORMS:
strobo·scopic (-skpk) —ADJECTIVE
strobo·scopi·cal·ly —ADVERB
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Carpal Tunnel
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wofa--I am i-m-pressed, all over the place! Tedster, I think you're right--though I am treading on very thin ice, in amongst all these medical professionals: I too seem to recall being taught that our eyes see "samples", and our brains fill in the blanks. I also believe we've had this topic (both, actually) before, but can't think of any efficient way to Search for it {them}.)
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OP
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> I too seem to recall being taught that our eyes see "samples", and our brains fill in the blanks
I too might tend toward this explanation. I know that we only see very clearly in the small central portion of our field of view and fill in the rest beyond the divide of our optical nerve.
Re. Strobes ... I was once told a story about a friendly old gentleman on a train. The man said that in the 20s or 30s he had sat outside a university in Switzerland and watched a queer bloke looking at a water fountain through his hand. Intrigued he asked the man what he was up to. He was told to notice that when one opens and closes one's fingers quickly while peering through them that the foutain seemed to stop moving. Shortly after the man was greeted by the person he was waiting for and left. At the same time a friend walked up and asked 'Did you know who that was?'. He was a bit bewildered to discover he'd been chatting to Albert Einstein :-)
Anyway, thanks for your explanation Faldage, but I'm not sure about the 'error' part - it looks right to me! I'll be interested to hear your friend's comments, Ted.
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by, if you are concerned about Faldage's use of the term "sampling error" be assured that he is correct. In sampling anything, there is a requirement that to prevent aliasing you must sample at a frequency beyond the "Nyquist frequency", which is twice the frequency of the maximum frequency you are interested in accurately reproducing. If there are frequency components higher than that in the process you are sampling, then they are "aliased" and it is indeed referred to as "sampling error". Anyway, with the wheel turning much faster (more than half as fast) than the movie frames are going by, you experience a real-life version of sampling error. I was trying to draw a nice graph on Matlab yesterday to help explain this but was sidetracked by "real" work.
A non-graphical example would be the sampling rate of CDs. The human ear is sensitive to sounds (on average) between 20 Hz and 20 000 Hz (20 kHz). So if I want to accurately reproduce the highest frequencies I can hear - the 20 000 Hz ones - I must sample at least twice as fast as that. So CDs are typically sampled at about 44 000 Hz (I think it might be 44 100), or there's another standard that calls for about 48 000 Hz. Both are twice as large as 20 000 Hz, so aliasing of audible frequencies shouldn't happen.
DISCLAIMER: Please don't start arguing with me about the sound of CDs and analog and why one is better than the other. I was just using the CD as a sampling-theory example.
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Thanks for your thorough description, Bean. I was more poking fun than anything else. As I see it this 'sampling error' is a great visualisation of the recapitulating, reciprocating, and symetrically duplicating process indicative to the nature of perception. I think that third object wofa mentioned does exist, you know[g]. But that's just me.
I hope you get that graph finished soon, btw!
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Carpal Tunnel
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From "engines" episode # 1183
"A stream of water flowed through the Leda scene.
And in the years just before he painted her,
Leonardo began his studies of moving water. Fluid
flow scholars call Leonardo the first student of
turbulent eddies. His drawings capture that motion
so well his vision must've been stroboscopic. The
water is more than just realistic. It seems alive. And
Leonardo later went from the study of moving water
to the study of blood flow in living beings. "
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Carpal Tunnel
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I ran across this a few days ago and bookmarked it since it bears on this discussion: http://www.yorku.ca/eye/balls.htm
TEd
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Carpal Tunnel
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Ted, what a fun site--thank you. This is from it, also; I found it under Fun Things. http://www.yorku.ca/eye/necker.htm
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