1080: "Visual Field"

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Re: 1080: "Visual Field"

Postby Angua » Wed Jul 11, 2012 12:53 pm UTC

Probably because your red cones get overstimulated (aka too 'bleached') from sunlight going through your eyelids, and that's about the amount of time for them to recover.
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Re: 1080: "Visual Field"

Postby dexeron » Wed Jul 11, 2012 1:03 pm UTC

WOW, I've been wondering for YEARS about those white squiggly things you can only see against a blue sky! It drives me nuts on a clear day. White cells in the blood vessels. Who knew?

(Apparently, lots of people, just not me!)

--

The best part of today's comic is that it reminded me of something ELSE that's been bothering me, and I finally looked it up. I've never met anyone else who's experienced it (in fact, people look at me like I'm crazy when I describe it) but when I I turn my head while looking at a colored light source (so that I end up seeing it out of the corner of my eye) the light source will often MOVE in relation to the background. In other words, looking at the little red "message" light on my desk phone... if I turn my head back and forth, the light will actually move left and right while the phone remains stationary! This is most pronounced with red lights, I think. Also, sometimes (depending on the kind of light) a light will actually seem to CHANGE color if moved away from the center of vision, changing from red to blue and back!

Turns out it's called Chromatic Abberation and it is, as I thought, the result of my glasses. It's probably more pronounced for me because of the extreme curvature of my lenses.

So I'm not actually going crazy. At least not in that way. ;)
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Re: 1080: "Visual Field"

Postby cellocgw » Wed Jul 11, 2012 1:13 pm UTC

reitsma wrote:brilliant comic, but it still hasn't addressed a strange visual phenomenon that I experience - if you stare at an LED clock, and 'crunch' on something (causing jaw, and i guess one's whole head to move), the glowing numbers 'jump' around independently.
does anyone else have this experience?

Yep, I've noticed that for years. I don't know why, but would guess that (once again!) you're observing "true" motion of the bright lights due to muscles moving your eyeball a bit, but your brain reconstructs all the dark, "boring" part of the image from memory, so it doesn't move. Just a semi-educated guess
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Re: 1080: "Visual Field"

Postby MisterCheif » Wed Jul 11, 2012 1:23 pm UTC

cellocgw wrote:
reitsma wrote:brilliant comic, but it still hasn't addressed a strange visual phenomenon that I experience - if you stare at an LED clock, and 'crunch' on something (causing jaw, and i guess one's whole head to move), the glowing numbers 'jump' around independently.
does anyone else have this experience?

Yep, I've noticed that for years. I don't know why, but would guess that (once again!) you're observing "true" motion of the bright lights due to muscles moving your eyeball a bit, but your brain reconstructs all the dark, "boring" part of the image from memory, so it doesn't move. Just a semi-educated guess


I think it has more to do with vibrations traveling up your jaw, and then the brain reconstructing the image. I used to use an electric toothbrush, and I'd get that "jump" while brushing my teeth, both looking at an LED clock, where the numbers would move independently of each other, and also with the entire image of a TV, moving around and sometimes actually overlapping onto the bezel.

It's kind of scary how much of your perception of vision in general is made up by guesses on the part of your brain.
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Re: 1080: "Visual Field"

Postby peewee_RotA » Wed Jul 11, 2012 1:24 pm UTC

All that I got from this one is that a watched pot boils faster than one you keep glancing at.
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Re: 1080: "Visual Field"

Postby orthogon » Wed Jul 11, 2012 1:31 pm UTC

cellocgw wrote:
reitsma wrote:brilliant comic, but it still hasn't addressed a strange visual phenomenon that I experience - if you stare at an LED clock, and 'crunch' on something (causing jaw, and i guess one's whole head to move), the glowing numbers 'jump' around independently.
does anyone else have this experience?

Yep, I've noticed that for years. I don't know why, but would guess that (once again!) you're observing "true" motion of the bright lights due to muscles moving your eyeball a bit, but your brain reconstructs all the dark, "boring" part of the image from memory, so it doesn't move. Just a semi-educated guess


It's probably because the LEDs are not on all the time, but instead are "scanned". Only one LED (or one row/column, or one digit, depending what the display is like) is lit up at any time, but your persistence of vision makes it appear that they are all on all the time. There are a couple of reasons for doing this: LEDs are generally more efficient when pulsed, and you can cut down on driver circuitry (e.g. use one transistor for each row and one for each column or one for each digit and each segment instead of one for each LED).

When you crunch your jaw, your head moves randomly, and is in a slightly different position when each of the LEDs is pulsed, so as a result each LED appears to be in a different position relative to the others.
Last edited by orthogon on Wed Jul 11, 2012 1:41 pm UTC, edited 1 time in total.
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Re: 1080: "Visual Field"

Postby Aubri » Wed Jul 11, 2012 1:33 pm UTC

Each of your eyes has over three million photoreceptors called "rods" and "cones".
These receptors convert light into electrochemical signals that travel through the optic nerve and into the brain.
Here, these signals trigger the neurological process scientists call... The Hellawack Shiznit That Happens Inside Your Brizzle.

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Re: 1080: "Visual Field"

Postby hermitian » Wed Jul 11, 2012 1:39 pm UTC

About the "same level of detail" on the right side...

If I look at the image appropriately, I can tell that the "level of detail" picture in the center is of two stick figures, the one on the right has more hair (or what appears to be dark blotting around the head).

Now, if I continue to look at the center, and pay attention to the right-most image in my peripheral vision, I can see that there are shapes there, but I am unable to "process" that there are two stick figures there, one with more hair.

In other words, If I was only given the picture on the left, I would have had a hard time describing the picture as containing two stick figures.

Am I the only one?

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Re: 1080: "Visual Field"

Postby Aubri » Wed Jul 11, 2012 1:46 pm UTC

Quicksilver wrote:What's a supermoon?

It's a full moon at perigee. Every time it happens, the media goes nuts even though it's only 14% bigger than an apogee full moon and the difference is not noticeable to the eye.

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Re: 1080: "Visual Field"

Postby morgothcr » Wed Jul 11, 2012 2:13 pm UTC

marsman57 wrote:I felt like I did it correctly, but I could see the blind spots without any problem. Did anyone else have this experience?

I think it's because each eye is compensating for the blind spot on the other one, so you really don't have a blind spot while looking with both eyes.
Try covering one eye at a time: The blind spot on the corresponding side magically, well, disappears...

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Re: 1080: "Visual Field"

Postby jonsimon » Wed Jul 11, 2012 2:17 pm UTC

jqubed wrote:
dzamie wrote:Hmm... Wikipedia doesn't really have too much about chronostasis aside from its name and description. Oh well.


So, basically, it's our brain's image stabilization initially not realizing the clock hand is still supposed to be moving?


No. When you move your eye too quickly, it proudcues a blur image for the milliseconds it took to move your eye. Because your brain doesn't bother processing the blur, it replaces those miliseconds in your visual memory with the image of the thing you moved to. Essentially, it rewrites the history of what you perceived.

Another cool sight/perception difference is backward or forward masking. In either case, you present a visual stimulus, like a green triangle, and present a second stimulus, like a yellow square, in the same spot either before (forward masking) or after (backward masking) the green triangle. If the two are presented in the same location, for a very short time, and within 50 milliseconds of each other, your eyes will see both stimuli, but your brain will not perceive the green triangle. We can prove your eyes register both stimuli because you will still react to the green triangle in a reaction time test, even though you won't ever remember seeing it. Once again, your brain has overwritten what your eyes have actually seen.

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Re: 1080: "Visual Field"

Postby AvatarIII » Wed Jul 11, 2012 2:21 pm UTC

Some people find the interiors of eyes funny, not me, I guess I just don't get vitreous humour.

[/badjoke]

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Re: 1080: "Visual Field"

Postby Jeff Bobbo » Wed Jul 11, 2012 2:33 pm UTC

orthogon wrote:It's probably because the LEDs are not on all the time, but instead are "scanned". Only one LED (or one row/column, or one digit, depending what the display is like) is lit up at any time, but your persistence of vision makes it appear that they are all on all the time. There are a couple of reasons for doing this: LEDs are generally more efficient when pulsed, and you can cut down on driver circuitry (e.g. use one transistor for each row and one for each column or one for each digit and each segment instead of one for each LED).

When you crunch your jaw, your head moves randomly, and is in a slightly different position when each of the LEDs is pulsed, so as a result each LED appears to be in a different position relative to the others.


It's what this guy said. The process which occurs in the device is a form of multiplexing (see http://en.wikipedia.org/wiki/Multiplexing & http://en.wikipedia.org/wiki/Multiplexed_display for more information). The persistence of vision (POV) effect of your eyes (caused by the fact that your eyes can only 'see so fast') means that normally, we don't see the display flicker. But if we're moving it's much easier to see. I personally notice this a lot from just walking past a clock or other display.

Your computer monitor, TV and pretty much anything with a display that has a refresh rate uses this technique, and while LEDs can be more efficient when pulsed, the real benefit from it (and why we use all multiplexing techniques) is to save input/output pins, which makes circuits cheaper.


The POV effect is the same sort of thing that can be responsible for when wheels on TV on cars appear to be going backwards/slow/not moving (although under a different name). A camera can't record a constant stream of video, it's just images taken close to each other (like a flick book). If a wheel on a car rotates just under a full revolution in the time between consecutive pictures are taken by the camera, when the video is played back the wheel will look like it's going backwards. See: http://en.wikipedia.org/wiki/Wagon-wheel_effect


----

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Re: 1080: "Visual Field"

Postby Max™ » Wed Jul 11, 2012 2:39 pm UTC

AvatarIII wrote:Some people find the interiors of eyes funny, not me, I guess I just don't get vitreous humour.

[/badjoke]

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Re: 1080: "Visual Field"

Postby dp2 » Wed Jul 11, 2012 2:51 pm UTC

radtea wrote:
RockoTDF wrote:Thanks for the teaching tool! Seriously, this belongs in a textbook.


The only issue is that it uses the word "see" to describe "the detailed physiology of what the eye does", which gets naive people confused into saying things like "you don't 'really see' colour in the periphery of your vision... your brain remembers what colour things are and fills it in for you", as if "the brain remembering what colour things are and filling it in for you" is by some ontological legerdemain not "really seeing". If it isn't seeing, what is it?

I was going to retort, but then I ... saw ... your point. I was going to say "seeing" implies that the object (or color or whatever) is actually there. But then, we also use "seeing" when something in fact isn't there, like a mirage or a hallucination.

But then, what term should be used? Is there a word or phrase you would use instead of "not really seeing" to say that someone believed they were seeing something that didn't exist outside their brain?

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Re: 1080: "Visual Field"

Postby Max™ » Wed Jul 11, 2012 3:04 pm UTC

dp2 wrote:
radtea wrote:
RockoTDF wrote:Thanks for the teaching tool! Seriously, this belongs in a textbook.


The only issue is that it uses the word "see" to describe "the detailed physiology of what the eye does", which gets naive people confused into saying things like "you don't 'really see' colour in the periphery of your vision... your brain remembers what colour things are and fills it in for you", as if "the brain remembering what colour things are and filling it in for you" is by some ontological legerdemain not "really seeing". If it isn't seeing, what is it?

I was going to retort, but then I ... saw ... your point. I was going to say "seeing" implies that the object (or color or whatever) is actually there. But then, we also use "seeing" when something in fact isn't there, like a mirage or a hallucination.

But then, what term should be used? Is there a word or phrase you would use instead of "not really seeing" to say that someone believed they were seeing something that didn't exist outside their brain?

Hallucination, illusion, ghost, spirit, ufo, magic, bigfoot, etc.
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Re: 1080: "Visual Field"

Postby Lynx Cat » Wed Jul 11, 2012 3:05 pm UTC

I'd say "what you see" and "what your eyes detect" to note the difference. The data that your eyes send to your brain is one thing (what your eyes detect), and the input your brain's "video card" sends to your consciousness is another (what you see). Since "seeing" is a reference to perception, and perception is anchored on consciousness, I'd use it to describe the impression you have about the visual input you get, with all "image processing" included.
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Re: 1080: "Visual Field"

Postby Fire Brns » Wed Jul 11, 2012 3:05 pm UTC

jqubed wrote:
dzamie wrote:Hmm... Wikipedia doesn't really have too much about chronostasis aside from its name and description. Oh well.


So, basically, it's our brain's image stabilization initially not realizing the clock hand is still supposed to be moving?

When your eyes dart rapidly your brain turns them off to avoid blurry images that trigger a sudden urge to vomit. So that you don't feel blind it retroactively erases the memory of being blind.

Actually before I continue: dart your eyes back and forth from the left side of the screen to the right and then back, see how your vision gets a little darker?

To fill that time in your memory where you were blind it takes the first image you see and uses ctrl-c ctrl-p to fill the gap in your memory.

--

As for the polarization, first confirm that your screen is polarized. I know LCD does it, cathode-ray is a no, plasma I'm unsure. If you don't know and have a pair of polarized glasses nearby hold the lense in front of the screen and rotate it until the lens blacks out the light. (at about 45 degree) They are making new polarized glasses so they don't do this -boat and plane crashes and all- so it isn't a garunteed test.
To test with your eyes, you need as pure white as you can get your screen. Open photoshop or paint for best results which still may be very faint especially with those white blood cells saying hi.
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Re: 1080: "Visual Field"

Postby omikun » Wed Jul 11, 2012 3:28 pm UTC

Randal, I love it!. But please apply a sharpen filter after you resize the image. That would make it much more readable without having to click through to a larger version.

Thanks.
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Re: 1080: "Visual Field"

Postby Richard Kirk » Wed Jul 11, 2012 3:35 pm UTC

This is pretty good.

We have no blue detectors in our macula (centre of vision). If we did, they would only be of limited use as they are under the yellow dye of the fovea (yellow spot). So the little image of the people at the centre of vision could be on yellow instead of white, and the blue part of the colour diagram should be black at the centre.

The blind spot is often much larger than it is drawn here. It appears often appears smaller because our eyes are usually twitching, and remembering the bits around the edges from when they were last visible. If you stop your eyes moving then most of the outside of the information will be lost, and our circle of vision will shrink to the macula.

If readers want to know more about the polarization bit, search on 'Haidinger's brushes'.

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Re: 1080: "Visual Field"

Postby ejono » Wed Jul 11, 2012 3:55 pm UTC

When I took a look at my analog clock just now, it took me a few seconds to realize that the battery had died, and the clock wasn't moving at all. :D

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Re: 1080: "Visual Field"

Postby dcheesi » Wed Jul 11, 2012 4:13 pm UTC

If you don't feel like cutting pieces of paper to length, another way to calibrate your viewing distance is to use the handy blind-spot indicators. Make an initial guess about the viewing distance (it's pretty short), then stare at the center point and close your eyes one at a time. Move your head closer/further from the screen, and at some point you should notice the corresponding blind-spot circle partially disappearing. When you've got it so that both blind spots are covering most of their respective circles, you should be at the proper distance.

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Re: 1080: "Visual Field"

Postby Angua » Wed Jul 11, 2012 4:35 pm UTC

Richard Kirk wrote:This is pretty good.

We have no blue detectors in our macula (centre of vision). If we did, they would only be of limited use as they are under the yellow dye of the fovea (yellow spot). So the little image of the people at the centre of vision could be on yellow instead of white, and the blue part of the colour diagram should be black at the centre.

The blind spot is often much larger than it is drawn here. It appears often appears smaller because our eyes are usually twitching, and remembering the bits around the edges from when they were last visible. If you stop your eyes moving then most of the outside of the information will be lost, and our circle of vision will shrink to the macula.

If readers want to know more about the polarization bit, search on 'Haidinger's brushes'.

Of course, one of the reasons the body filters out the blue from the fovea is due to the fact that red and green are nice and close together, so you get less difference in focusing them as different wavelengths focus differently. It also helps increase the resolution as you only have to go two cells apart rather than 3.
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Re: 1080: "Visual Field"

Postby wappentake » Wed Jul 11, 2012 4:53 pm UTC

MisterCheif wrote:
cellocgw wrote:
reitsma wrote:brilliant comic, but it still hasn't addressed a strange visual phenomenon that I experience - if you stare at an LED clock, and 'crunch' on something (causing jaw, and i guess one's whole head to move), the glowing numbers 'jump' around independently.
does anyone else have this experience?

Yep, I've noticed that for years. I don't know why, but would guess that (once again!) you're observing "true" motion of the bright lights due to muscles moving your eyeball a bit, but your brain reconstructs all the dark, "boring" part of the image from memory, so it doesn't move. Just a semi-educated guess


I think it has more to do with vibrations traveling up your jaw, and then the brain reconstructing the image. I used to use an electric toothbrush, and I'd get that "jump" while brushing my teeth, both looking at an LED clock, where the numbers would move independently of each other, and also with the entire image of a TV, moving around and sometimes actually overlapping onto the bezel.

It's kind of scary how much of your perception of vision in general is made up by guesses on the part of your brain.

Yes, that's it exactly. Google "Frito effect."

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Re: 1080: "Visual Field"

Postby San Fran Sam » Wed Jul 11, 2012 4:57 pm UTC

this is all well and good but could someone explain to me why when an anvil is dropped on my head sometimes i see stars and sometimes i see birds?

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Re: 1080: "Visual Field"

Postby blowfishhootie » Wed Jul 11, 2012 5:03 pm UTC

San Fran Sam wrote:this is all well and good but could someone explain to me why when an anvil is dropped on my head sometimes i see stars and sometimes i see birds?


Just depends on the sense of humor of the cartoonist that has drawn you into creation on that given day.

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Re: 1080: "Visual Field"

Postby RebeccaRGB » Wed Jul 11, 2012 5:18 pm UTC

dexeron wrote:Turns out it's called Chromatic Abberation and it is, as I thought, the result of my glasses. It's probably more pronounced for me because of the extreme curvature of my lenses.

So *that's* what's happening. I get that too, especially against a black background. On an LCD display, different colors will "pop" out at different "depths." On an LED array, if I turn my head, they'll appear in different places.
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Re: 1080: "Visual Field"

Postby keithl » Wed Jul 11, 2012 5:19 pm UTC

orthogon wrote:
reitsma wrote:brilliant comic, but it still hasn't addressed a strange visual phenomenon that I experience - if you stare at an LED clock, and 'crunch' on something (causing jaw, and i guess one's whole head to move), the glowing numbers 'jump' around independently.
does anyone else have this experience?


It's probably because the LEDs are not on all the time, but instead are "scanned". Only one LED (or one row/column, or one digit, depending what the display is like) is lit up at any time, but your persistence of vision makes it appear that they are all on all the time. There are a couple of reasons for doing this: LEDs are generally more efficient when pulsed, and you can cut down on driver circuitry (e.g. use one transistor for each row and one for each column or one for each digit and each segment instead of one for each LED).

When you crunch your jaw, your head moves randomly, and is in a slightly different position when each of the LEDs is pulsed, so as a result each LED appears to be in a different position relative to the others.


A good explanation, though the "pulsed efficiency" part can be misunderstood. AC-powered devices have a rectifier that converts the power line sine wave into a series of absolute value bumps: ⌒⌒⌒⌒⌒⌒ (full wave) or ⌒—⌒—⌒— (half wave) (Unicode graphics). To save money, they don't add a capacitor to smooth out the bumps powering the LEDs (they do have a much smaller capacitor smoothing out the bumps for the clock chip). The clock scans the LEDs slowly enough so that each bump powers one of the seven segments. The pattern repeats at a full wave 120/7 ≌ 17 Hz. Or sometimes 120/4 for 4 digits, or 120/8 because a divide by 7 is more complicated than a divide by 8. The details vary for different clock chips. Since a halfwave rectifier needs only one diode, while a fullwave rectifier needs 4, they save another 5 cents by using every other rectified bump, dividing all the above frequencies by two. Thus, LED clocks scan slower than a screen (typically 60Hz or faster) so the artifacts are more noticable.

BTW, another note on LED clocks - if you can still find them, get red LED clocks for bedroom and nighttime bathroom. Green and blue stimulate the brain so that it is harder to get back to sleep. I'm fanatic enough to rewire the resistors in the clock so that the nighttime dim switch makes them Really Dim, though this sometimes makes the segments look a little uneven.

Edit: I also have a separate red CFL in an overhead fixture for the bathroom, a small red LED shining on the toilet bowl to improve nocturnal aim, replaced the green LED in my cell charger with a red one, and taped over the green LED on the GFCI outlet. I am fanatic about this "red light at night" thing,

Making consumer goods cheaper and cheaper, until they behave on the threshold of visual annoyance, is another "benefit" of understanding visual perception. Why pay extra for quality when you can get more "features" instead?
Last edited by keithl on Wed Jul 11, 2012 5:31 pm UTC, edited 1 time in total.

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Re: 1080: "Visual Field"

Postby battlesnake » Wed Jul 11, 2012 5:21 pm UTC

In some cases (although definitely not for 100% of people), some of the mysterious floaters are the remains of the Hyaloid Artery, which supplied the front of the eye with blood during its early development - look up "persistent hyaloid" for the associated medical diagnosis.

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Re: 1080: "Visual Field"

Postby Max™ » Wed Jul 11, 2012 5:22 pm UTC

Can't you just put a bit of suitably colored plastic in front of the clock and make it red to prevent the green/blue wakefulness issue?

I mean, sure, rewiring it is geeky fun... but a bit excessive.
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Re: 1080: "Visual Field"

Postby PhDFluff » Wed Jul 11, 2012 5:26 pm UTC

This explains why blue neon signs are incredibly hard to focus on and sometimes even impossible to read.

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Re: 1080: "Visual Field"

Postby highlyverbal » Wed Jul 11, 2012 5:39 pm UTC

Everyone seems to have their fun vision facts to add to the mix! Here's mine:

Due to the overlap of wavelengths detected in cone cells in the eyes, there is the possibility of Imaginary Colors (google it!).

Quick summary: at some point in the future we will be able to stimulate neurons (or cones) without an external stimulus. At that point, stimulate one of the cones that sees "green" but not the other one! This hemi-green is an imaginary color in the sense that no natural phenomenon produces it or even could (light at that wavelength would strike and stimulate all relevant cones). What will your brain perceive then? What will that feel like?

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Re: 1080: "Visual Field"

Postby Coyoty » Wed Jul 11, 2012 5:44 pm UTC

dp2 wrote:
radtea wrote:
RockoTDF wrote:Thanks for the teaching tool! Seriously, this belongs in a textbook.


The only issue is that it uses the word "see" to describe "the detailed physiology of what the eye does", which gets naive people confused into saying things like "you don't 'really see' colour in the periphery of your vision... your brain remembers what colour things are and fills it in for you", as if "the brain remembering what colour things are and filling it in for you" is by some ontological legerdemain not "really seeing". If it isn't seeing, what is it?

I was going to retort, but then I ... saw ... your point. I was going to say "seeing" implies that the object (or color or whatever) is actually there. But then, we also use "seeing" when something in fact isn't there, like a mirage or a hallucination.

But then, what term should be used? Is there a word or phrase you would use instead of "not really seeing" to say that someone believed they were seeing something that didn't exist outside their brain?


Interpolation.

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Max™
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Re: 1080: "Visual Field"

Postby Max™ » Wed Jul 11, 2012 5:48 pm UTC

highlyverbal wrote:Everyone seems to have their fun vision facts to add to the mix! Here's mine:

Due to the overlap of wavelengths detected in cone cells in the eyes, there is the possibility of Imaginary Colors (google it!).

Quick summary: at some point in the future we will be able to stimulate neurons (or cones) without an external stimulus. At that point, stimulate one of the cones that sees "green" but not the other one! This hemi-green is an imaginary color in the sense that no natural phenomenon produces it or even could (light at that wavelength would strike and stimulate all relevant cones). What will your brain perceive then? What will that feel like?

Spoiler:
Image
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keithl
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Re: 1080: "Visual Field"

Postby keithl » Wed Jul 11, 2012 5:51 pm UTC

Max™ wrote:Can't you just put a bit of suitably colored plastic in front of the clock and make it red to prevent the green/blue wakefulness issue?

I mean, sure, rewiring it is geeky fun... but a bit excessive.


The clock rewiring is for dimness, and yes, a suitable attenuating filter will do that too, but I have a lot more resistors around than optical filter material. I like opening things up and poking around in them with an oscilloscope. I even replaced my laptop screen with a 2048x1536 screen (and hacked EDID EEPROM) that Lenovo doesn't support. Void all warranties. Nothing exceeds like excess.

Turning green/blue into red? Not unless the source is actually white. There aren't any red photons in green or blue light, though some electroluminescent panels are broad spectrum with peaks in the blue/green. I can imagine a dye filter stimulated by higher energy photons to emit red photons, but I don't know where to buy such a filter, and inventing it would be WAY more geeky than I can manage. This forum being übergeek xkcd fans, I will probably get one in the mail. Thanks in advance!

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Max™
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Re: 1080: "Visual Field"

Postby Max™ » Wed Jul 11, 2012 5:57 pm UTC

Meant redder, I'm up waiting on a call so I'm kinda groggy.
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Shadowman615
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Re: 1080: "Visual Field"

Postby Shadowman615 » Wed Jul 11, 2012 6:02 pm UTC

dzamie wrote:Hmm... Wikipedia doesn't really have too much about chronostasis aside from its name and description. Oh well.


Here's a nice explanation:
http://www.youtube.com/watch?v=nNBTLbw1_2Q

Timst
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Re: 1080: "Visual Field"

Postby Timst » Wed Jul 11, 2012 6:27 pm UTC

Alright, so the floaters have an explanation. On to another thing that bug me since childhood: Am I the only one, at night (or I guess anytime it's completely dark), to see the dark not uniformly black, but rather composed of a myriad of tiny color pixels on a black background? I mean it's not like a confetti party or anything, but it's not just a black shape either. When I focus at the center of my field of vision I can even see some kind of spinning diamond shape, and I remember observing it since I was a child. Ol' diamond, I call him.

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Re: 1080: "Visual Field"

Postby jpers36 » Wed Jul 11, 2012 6:31 pm UTC

Somewhat tangential, but I have voluntary nystagmus.

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Nexxo
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Re: 1080: "Visual Field"

Postby Nexxo » Wed Jul 11, 2012 6:32 pm UTC

I have just been awesomed.


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