4d Visible To Human Eyes?

[Ken]

Huh? the 2 images are combined and the distance to each point is calculated in the brain producing a 2.5D image.

 

 

Not to be argumentative but that isn't the way you stated it. You said the pixels were encoded with the distance from us. Your revision is closer to the mark, but I'm afraid you have it backwards.

 

The images are compared, the disparity entered into the interpretation, and a neural representation of the two images fused together is "created".

 

We still don't know how the neural events become translated into some kind of experience, but the receptors, the transduction into neural impulses, the pathways the nerves follow, and the analysis in the layers of the visual cortex are pretty well understood. We know how information is received by the eye, and augmented by the neurophysiology of the retina to sharpen images, encode frequency or wavelength, and increase or decrease sensitivity under different levels of illumination. Pretty much all of the remaining analysis and interpretation takes place in the head end of the Central Nervous System.

 

I realize that it's easy to conceptualize it in terms of Pixels, but the receptors of the eye are unlike any other form of Pixels. They vary in size, in spectral sensitivity, and in the extent of convergence. In some parts of the retina the rods converge more than a thousand rods to a single cell that transmits along the optic nerve while in the cones convergence ranges between 10:1 to 1:1. That essentially means that in the case of many rods information from over a large area and number of rods leads to just a single set of impulses along one nerve fiber. Under those conditons its impossible to determine which rod was stimulated and the effect is that we perceive less retinal disparity between the rods of one eye and the other.

[granpa]

Not to be argumentative but...

Too late

[Ken]

Too late

 

 

:D :D

 

Perhaps I should have said "...not to be offensive but..." or "...not to be disrepectful..." ;)

 

My "argument" was that your model of perception, while novel, is not in accord with the anatomy and physiology of the visual system.

 

Your model involving pixels is part of the concept of Raster Images. A quick definition (from the WiseGeek) website is:

 

"A raster image, also called a bitmap, is a way to represent digital images. The raster image takes a wide variety of formats, including the familiar .gif, .jpg, and .bmp. A raster image represents an image in a series of bits of information which translate into pixels on the screen. These pixels form points of color which create an overall finished image.

 

When a raster image is created, the image on the screen is converted into pixels. Each pixel is assigned a specific value which determines its color. The raster image system uses the red, green, blue (RGB) color system. An RGB value of 0,0,0 would be black, and the values go all the way through to 256 for each color, allowing the expression of a wide range of color values. In photographs with subtle shading, this can be extremely valuable. "

 

That model is based on an implicit assumption that the sensei or sensory pixels are arranged in a precise grid pattern. That assumption does not match the anatomy of the retina.

 

You obviously understood the concept of retinal disparity, you just got a little off track the details.

 

Cheers,

[granpa]

:D :D

Your model involving pixels is part of the concept of Raster Images. A quick definition (from the WiseGeek) website is:

 

That model is based on an implicit assumption that the sensei or sensory pixels are arranged in a precise grid pattern. That assumption does not match the anatomy of the retina.

 

 

It may not match the way the outer parts of the retina is encoded but it does match the inner part. (the Fovea)

I personally am not aware of any sense of depth perception in the outer parts of my vision.

[Ken]

It may not match the way the outer parts of the retina is encoded but it does match the inner part. (the Fovea)

I personally am not aware of any sense of depth perception in the outer parts of my vision.

 

 

My last comment.

 

The fovea centralis is at the focal point of the optical system, and stays that way as the eye moves to direct stimuli of import to that region. The fovea is the only all-cone region of the eye. Receptors in the fovea have the lowest convergence of any visual units, ranging from 10:1 to 1:1. Information is coded in two different ways, binary (0ff/On) and analog (s potentials). Neither of those codes provides depth information. They only provide information which the cerebral cortex analyzes, measuring retinal disparity (the differences in composite images from each eye) to allow judgements about distance. The more the messages from the two eyes differ, the more depth is perceived.

 

The tight packing of cones in the fovea gives rise to the greater acuity of that region so that more detail is available for making comparisons between the different images. The operative term in physical optics is parallax, in physiological optics it's retinal disparity.

 

The single eye cues, monocular cues, are much less accurate and more easily distorted or confused. The two eye cues work because the dual outputs are analyzed "higher up" outside the eyes.

 

 

:D

[granpa]

Neither of those codes provides depth information. They only provide information which the cerebral cortex analyzes, measuring retinal disparity (the differences in composite images from each eye) to allow judgements about distance.

 

I know. Thats what I said.

[Kharakov]

Does Anableps anableps (the four-eyed fish) exist in, or see in 4 dimensions? Do spiders live and see in 8 dimensions?

Of course there are exceptions (it wasn't a serious comment, and neither is this first paragraph of my response). Consider the fact that the 2 "sets" of eyes in the fish are used to view above and below the waterline and in spiders the secondary eyes are mostly used to sense from which direction light is coming (perhaps to detect light coming from prey's eyes?). So in both cases the extra eyes serve purposes other than that of being used to form a compound mental image for depth perception (into the 4th or higher dimension). Also, by extrapolation of the first idea, the spiders 2 sets of 4 eyes (assuming they all worked to detect perspective rather than 6 being primitive light detectors, photons traveled in 4+ space dimensions, etc..) would detect depth differences in the 5th dimension. Anyways....

 

 

The lack of "photon loss" in experiments should indicate that photons don't veer away from our 3 dimensions of space. There would be a noticeable decrease in number of photons detected in various experiments if photons also "traveled" off in a 4th spacial direction (never to intersect with out 3 dimensions again, unless reflected back, but in this case wouldn't we have been detecting photons from the 4th dimension frequently beforehand?).

 

There would have to be a 4th dimensional photon equivalent (including other forms of 4th dimensional energy and matter), which would not interact with 3 dimensional matter/energy for the same reason 3 dimensional matter/energy doesn't interact with 2 dimensional matter: 2 dimensional matter is effectively infinitely small (zero volume or nil sized) when compared to 3 dimensional matter (which has volume).

 

To extrapolate from this idea:

 

3 dimensional matter wouldn't directly interact with 4 dimensional matter for the simple reason that it has zero 4 dimensional volume, which explains Dark Matter and Dark energy not directly interacting with 3 dimensional matter (besides gravitationally **). Likewise, extend this up through the dimensions and you will see that 5 dimensional matter/energy does not directly interact with 4, 3, 2, or 1 dimensional matter/energy, etc. etc....

 

** I don't think it would interact with other forces, simply due to the requirement of specific 3d orientation/structure for electromagnetism, etc. which would extend up to there being specific 4d orientation/structure for 4 dimensional electromagnetism, etc. Not much thought given to this tangent as of yet, although it seems that perhaps gravitation is the one fundamental force, offhand, that I would think able to apply across all dimensions due to its lack of specific orientation within dimensions.

 

Seriously, what is your mu/tau dimension? Is it anything more than a mathematical derivation? If my simplistic notion that it is time is close to correct then you need to know that time plays a part in the interpretation of visual data.

Not time. Another dimension of space, with left/right directions being termed mu and tau respectively for lack of better terms. Of course, there would always need to be an additional dimension of time (for any # of dimensions of space), for the experience of "seeing" something to occur. Perhaps, from the deific perspective, the whole thing is always the same. In other words our 4 dimensional universe, which to us is experienced as 3 dimensions of space with time, would be a single unchanging 4 dimensional object from the deific perspective (in other other words, our dimension of time is a dimension of space from the deific perspective).

 

*in other other words is a tribute to the other other white meat.

 

Those images are exquiste. Bravo!!

Thanks. :D Just discovered a new 3d Mandelbrot (perhaps the right formula?) that works far better than the Mandelbulb for z^2 last night:

This first, and the next 4 images if you click the right arrow, are images of the z^2 (only 3d) Brots I have written.

 

All of this is a long way around to suggest that the human eye doesn't see three dimensions but rather that it detects differences in retinal disparity and several monocular cues and interprets those cues to allow judgements about depth (distance). If you could fabricate a true 4-Dimensional object the human eye would detect some aspects of it. Those aspects would include retinal disparity, height in a plane, variations in optical sharpness (aerial perspective), etc.

I can certainly detect the varying distance of objects by the feeling of my lens focusing (when I focus my mind upon the sensation). Normally I don't pay attention to the sensation, but it plays a substantial role in my perception of depth. Even with one eye closed, I can still tell (barring a few optical illusions designed to twist the mind) the relative distance of objects when I scan through them (whether they are closer or farther). Of course, this does not work with a 2d image (as you, in whatever field you are in, apparently know a lot about).

 

So I can tell the depth of an object by the lens contraction required to bring it into focus (to a certain extent). When I look at stuff, my brain interprets whether objects are closer or farther by interpreting when objects come into focus as the lens adjusts upon the focal point.

 

Those objects which come into focus when the lens is focused too close are closer than the object.

 

Those objects that come into focus when the lens is focused too far are farther than the object.

 

The objects that become more focused (yet are not completely focused when the object is sharp) as the lens focuses farther out are interpreted as farther than the object.

 

Those objects that become less focused as the lens focuses farther out upon the object are interpreted as closer than the object (by the mind/brain).

 

The thing is, I don't think we need 2 eyes for our mind to see in 3 dimensions, rather we simply need a 3d scenario in which to focus. Or better yet, the next generation of 3 dimensional holographic images will simply be 2d images that trick the mind into thinking the eye(s) focused upon a single point in the image!

[Proudclod229]

All the platonic solids...it's called metatron's cube.

[HydrogenBond]

The eyes alone can not tell the difference between a good 2.5-D spatial illusion, like the blue ball above and an actual 3-D blue ball. One needs to add another sense, such as the sense of touch, to touch the screen or touch the 3-D object to make sure it has 3-D depth. If you go to a 3-D movie, it can fool the eyes. But if you touch the screen or try to touch the dinosaur that appears in your face, you can see through the 2.5-D illusion. But the eyes can be fooled.

 

The range between 2.5-D and 3-D can be understood as relief drawings. Some of the shadowing and highlighting that makes the 2.5-D spatial illusions look 3-D, becomes actual depth, but is not enough depth to completely define the true 3-D nature of the full object. At 3- -D, that is still a tiny flat spot on the back of the 3-D ball. To see that flat spot, one need to moves around the ball in 3-D, using the sense of touch, for example, to find the flat spot. From certain angles one also can be fooled as 3-D, even with touch.

 

As we go from 3-D to 3+- D, a time element is added to the 3-D ball. Say the object changed colors because of the warmth of our touch, it would be 3+-D. Time is often defined as a change of state which in the this case, is a change in the state of actual 3-D object. As we approach 4-D, it would take infinite time to notice the change within the 3-D object. In the middle at 3.5-D, it would take a lifetime. At 3.5+ -D, the change would extend beyond our lifetime.

 

Based on how the brain works to perceive physical reality, the brain also uses this organization to define how we perceive intellectual reality. In this case, 2-D object is the plane of cause and effect, which we can see in the mind. But as we approach 2.5-D, emotional shadowing and highlighting can be used to create the illusion of 3-D (spatial truth that applies to all). To be able to tell the difference between 2.5-D and 3-D, one also needs something analogous to touch, to see through the emotional shadowing. That is called intuition. One has a gut feeling the 3-D dinosaur is not in the room but is an illusion even if logic seems to say it is. The logical mind may be fooled, if they don't use another sense, such as their common sense. The magician sets up the state so cause and effect appear to be satisfied. You need something else to see where it breaks down.

 

As we go from 2.5-D toward 3-D, the mental images because intuitive relief drawings, where the illusions of emotional appeal that can fool the logical mind (political parties) becomes depth of understanding. The entire data is contain in both illusions, not one or the other. This removal of the shadowing of the denial of truth becomes depth of understanding.

[Ken]

The eyes alone can not tell the difference between a good 2.5-D spatial illusion, like the blue ball above and an actual 3-D blue ball. One needs to add another sense, such as the sense of touch, to touch the screen or touch the 3-D object to make sure it has 3-D depth. If you go to a 3-D movie, it can fool the eyes. But if you touch the screen or try to touch the dinosaur that appears in your face, you can see through the 2.5-D illusion. But the eyes can be fooled.

 

The range between 2.5-D and 3-D can be understood as relief drawings. Some of the shadowing and highlighting that makes the 2.5-D spatial illusions look 3-D, becomes actual depth, but is not enough depth to completely define the true 3-D nature of the full object. At 3- -D, that is still a tiny flat spot on the back of the 3-D ball. To see that flat spot, one need to moves around the ball in 3-D, using the sense of touch, for example, to find the flat spot. From certain angles one also can be fooled as 3-D, even with touch.

 

As we go from 3-D to 3+- D, a time element is added to the 3-D ball. Say the object changed colors because of the warmth of our touch, it would be 3+-D. Time is often defined as a change of state which in the this case, is a change in the state of actual 3-D object. As we approach 4-D, it would take infinite time to notice the change within the 3-D object. In the middle at 3.5-D, it would take a lifetime. At 3.5+ -D, the change would extend beyond our lifetime.

 

Based on how the brain works to perceive physical reality, the brain also uses this organization to define how we perceive intellectual reality. In this case, 2-D object is the plane of cause and effect, which we can see in the mind. But as we approach 2.5-D, emotional shadowing and highlighting can be used to create the illusion of 3-D (spatial truth that applies to all). To be able to tell the difference between 2.5-D and 3-D, one also needs something analogous to touch, to see through the emotional shadowing. That is called intuition. One has a gut feeling the 3-D dinosaur is not in the room but is an illusion even if logic seems to say it is. The logical mind may be fooled, if they don't use another sense, such as their common sense. The magician sets up the state so cause and effect appear to be satisfied. You need something else to see where it breaks down.

 

As we go from 2.5-D toward 3-D, the mental images because intuitive relief drawings, where the illusions of emotional appeal that can fool the logical mind (political parties) becomes depth of understanding. The entire data is contain in both illusions, not one or the other. This removal of the shadowing of the denial of truth becomes depth of understanding.

 

I am completely bewildered by your references to 2.5D and 3.5D. In geometric terms what is a .5D, how would you plot it as an axis?

 

Depth perception is based on both monocular and binocular cues. The binocular cues use the disparity of images between two receptors in a plane perpendicular to the object in space. For the interocular distance of the average human that gives a reliable discrimination limit between the two images from about 15ft to possibly 30ft. Beyond those distances the image differences are just too small to be detected given the resolution of the optics in the eye. Some animals do much better than humans, some not as good.

 

The monocular cues are varied. Some are quite subtle and some extremely obvious. Someone previously (you?) suggested accommodation cues - sensing the contractions of the ciliary muscles as they change the optics of the lens. I'm not sure that cue is available and even if so it would be minimal compared to the huge effect of retinal disparity. Further the optics of the system put optical infinity out about 15 to 20 feet, i.e., anything beyond that point is at the same focus as an image at infinite distance.

 

A substantial cue is relative size. "Knowing" the real size of an object allows us to compare its size with some other object of known size. The relative sizes give us a clue as to which is closer. Think of the TV ads with giant humans walking along city streets. When the image of the human is larger than a 10 story building, you "know" he/she is taller.

 

Now put the images side by side. The large man on one side and the smaller image of a city on the other side and suddenly you perceive a normal sized man in the foreground and a very large city-scape in the far distance. It works even better if you place the feet of the man lower in the image than the base of the city - height in a plane is a strong distance cue.

 

Improve the effect by showing great detail in the image of the man and slightly blur the details of the city - gradient of texture another monocular cue.

 

Improve it further, for humans with intact color vision, by changing the color tint of the city image to a slightly more grayish-blue and you have added Aerial Perspective...

 

And I haven't even mentioned Superposition - when one image partially obscures your view of another image. ;)

 

If one really wants to push the essentially metaphysical notion of a time dimension then what we see in that 4th "dimension" is a finite series of successive images sampled from an infinite number of planes or transverse sections of the time flow - like the frames of a movie. I accept that this can be expressed mathematically as "seeing 4-D" but as a materialist I find it far too abstract. :D

[granpa]

2.5D is a way of referring to a 2D picture with the addition of a depth value for each pixel. (calculated from 'binocular cues' using the 'disparity of images')

 

The post above is an obvious troll post attempting to discredit the idea of 2.5D with a strawman argument. (emotional shadowing??? WTF?)

[Ken]

2.5D is a way of referring to a 2D picture with the addition of a depth value for each pixel. (calculated from 'binocular cues' using the 'disparity of images')

 

The post above is an obvious troll post attempting to discredit the idea of 2.5D with a strawman argument. (emotional shadowing??? WTF?)

 

 

What does this "pixel depth value" produce? Is it a dual image displaced across the plane of an image on a screen? or what?

 

Edit: I went back and read your prior post and my response. I should have asked then, and I do now, how is this depth value neurologically encoded for the brain to utilize and how would that be an improvement to direct comparison of disparate images from the two eyes?

 

To make sense for human depth perception the screen image analogy must conform to the actual neurophysiology of the nervous system.

:EndEdit

 

How is it related to natural human vision? Is anyone ever really fooled by it to the point that they can't discriminate between such images and real three dimensional images?

 

Perhaps I'm "guilty" of Professional shadowing. :D My post-graduate work centered on Sensory Psychology and Sensory Physiology with an emphasis on the visual senses.

 

I'm not sure if I can successfully embed a YouTube video on this site but I'll give it a try with a non-pixellated example of the monocular cues that give amazing perceptions of depth, if seen from the right position.

 

 

That didn't seem to work. :( I'll look around at the Help topics and either fix it or just put in the YouTube url.

 

Well, let's try this:

 

 

You'll note that no "depth value" was added to any pixels to provide a 3-dimensional perception without the use of special glasses. :)

[Ben]

What? You never heard of the [imath]\frac{1}{2}[/imath]-th dimension? Shame on you! Next you'll say you never heard of the [math]\pi[/math]-th dimension or the [math]e[/math]-th dimension....

 

What a troll.

 

PS This a Math and Physics forum. "Dimension" here has a rather exact meaning.

[Ken]

What? You never heard of the [imath]\frac{1}{2}[/imath]-th dimension? Shame on you! Next you'll say you never heard of the [math]\pi[/math]-th dimension or the [math]e[/math]-th dimension....

 

What a troll.

 

PS This a Math and Physics forum. "Dimension" here has a rather exact meaning.

 

 

The original question asked about Human Perception. That's no longer Math and Physics, its Physiological Optics, Neuroanatomy, and Neurophysiology.

 

If you wish to debate along insular disciplinary lines that are irrelevant to the Perception of depth then have at it. Math will not answer the OPs question.

 

I'll leave you folks to your knitting.

[Kharakov]

The monocular cues are varied. Some are quite subtle and some extremely obvious. Someone previously (you?) suggested accommodation cues - sensing the contractions of the ciliary muscles as they change the optics of the lens. I'm not sure that cue is available and even if so it would be minimal compared to the huge effect of retinal disparity. Further the optics of the system put optical infinity out about 15 to 20 feet, i.e., anything beyond that point is at the same focus as an image at infinite distance.

The accommodation cues were suggested (brought up) by me, not H-bond.

 

Funny thing was, while doing the test on myself, I thought (remembered) one tree was farther away than another, but the sensation of accommodation and corresponding automatic subconscious analysis told me differently (and was correct). The subconscious mental analysis could have taken into account other factors (shadows, occlusion, etc.) and caused me to perceive an illusory feeling of accommodation. The other possibility is that (relaxation of) accommodation, for some individuals, has a greater impact on depth perception than previously detected in experiments.

 

I'll have to do more self testing in the daylight hours, although I might forget about this for a few days as I have a rather busy schedule through the weekend. I'm curious as to why I "felt" it was the focusing of my eyes, rather than something else? I remember being quite shocked to find that what I was "told" by my eyes (about the depth of the trees) was more accurate than my recollection of the depth of the trees (been glancing at the same trees for 20+ years... so it was quite shocking- although I did pick trees a bit farther out than the ones I usually focus upon while watching birds/squirrels).

[Ken]

The accommodation cues were suggested (brought up) by me, not H-bond.

 

Funny thing was, while doing the test on myself, I thought (remembered) one tree was farther away than another, but the sensation of accommodation and corresponding automatic subconscious analysis told me differently (and was correct). The subconscious mental analysis could have taken into account other factors (shadows, occlusion, etc.) and caused me to perceive an illusory feeling of accommodation. The other possibility is that (relaxation of) accommodation, for some individuals, has a greater impact on depth perception than previously detected in experiments.

 

I'll have to do more self testing in the daylight hours, although I might forget about this for a few days as I have a rather busy schedule through the weekend. I'm curious as to why I "felt" it was the focusing of my eyes, rather than something else? I remember being quite shocked to find that what I was "told" by my eyes (about the depth of the trees) was more accurate than my recollection of the depth of the trees (been glancing at the same trees for 20+ years... so it was quite shocking- although I did pick trees a bit farther out than the ones I usually focus upon while watching birds/squirrels).

 

 

It's quite possible that you did experience this but I'm not familiar with any substantive research on it. Casual experience is that I'm aware when I'm trying to focus (Snellen Eye Chart, etc.) but I think that I'm aware of the effort to focus rather than the actual muscular activity.

 

It's an interesting question and I'm curious as to what you will think after you self-test.

 

Just one further point - I'm not a "fan" of sub-conscious explanations, at best they are a misleading description of autonomic functions, at worst they lead to a lot of metaphysical baggage that moves discussion away from objective data on receptor chemistry, organization, transduction, neural coding, etc. I unhappily accept that others may see this differently. :)

[Kharakov]

It's quite possible that you did experience this but I'm not familiar with any substantive research on it. Casual experience is that I'm aware when I'm trying to focus (Snellen Eye Chart, etc.) but I think that I'm aware of the effort to focus rather than the actual muscular activity.

 

It's an interesting question and I'm curious as to what you will think after you self-test.

On re-testing, I think the more likely explanation is that other clues (branches in front or behind, etc.) made me realize the one tree was in front of the other, but I was concentrating on focusing at the time which caused my incorrect crediting of accommodation rather than other cues.

 

Just one further point - I'm not a "fan" of sub-conscious explanations, at best they are a misleading description of autonomic functions, at worst they lead to a lot of metaphysical baggage that moves discussion away from objective data on receptor chemistry, organization, transduction, neural coding, etc. I unhappily accept that others may see this differently. :)

I wasn't really referring to autonomic functions, rather behaviors that have become so familiar to the conscious mind (such as walking) that they are carried out without conscious effort or (very much) awareness. Better term?