Anybody know? *smile*

- Shannon W. Rawls

None. Unless you jab yourself with a sharp jpg.

But seriously folks...

I've heard the number 8k bandied about. 35mm is "about" 4k, is it not?

I meant 8k resolution equivalent.

About 576 Megapixels according to Clarkvision Photography. Go to:

http://clarkvision.com/imagedetail/eye-resolution.html

I read through that page, and the "numerical equivalents" are stupid.

The eye is actually a very very bad camera, with the luminosity information provided by the rods, and the colour information provided by the cones (or is it the other way around?).

While it is quite sensitive to low light (basically the eye can count single photons) the aperture is rediculously small, making it quite inefficient at light gathering. The lenses are pretty low quality.

However, thanks to the amazing software provided by the brain, the eyes scan all over the place and "pixel-shift" like crazy to sample edges, resolve fine detail and increase the perceived resolution. I've seen a video of the rods and cones on the retina trying to resolve a light pattern projected by a laser in the last physics conference I went to. It's amazing how erratic the eye movement is. Imagine if you were to take a jackhammer to your video camera - that's pretty much what your eye does.

In addition, while the FOV of the eye is very large (~nearly 180 thanks to peripheral vision), you can only focus and resolve detail in a very small area at any one time. Your brain fools you into believing the rest of the world is that sharp, by resolving it when you choose to look there.

Personally, I think the best answer is that resolution is meaningless in the context of the eye. How long would it take you to resolve 1 line pair per mm at a distance of 1 foot? If it takes more than 1/60th of a second, how can you even compare this to a video or a still camera?

I remember reading somewhere that to reproduce a similar image of a high quality 35mm film camera you would need an 80 MegaPixel digital camera! I will see if I can find it again but it was a pretty old article, probably written during the early stages of digital photography.

"The eye is actually a very very bad camera...the aperture is rediculously small....the lenses are pretty low quality."

And for the life of me I can't figure out how to turn off the 'auto white balance' feature!

:)

Yeah, but you've gotta love the built-in 3D feature, not to mention native 16:9.

<<<-- Originally posted by Chris Hurd : Yeah, but you've gotta love the built-in 3D feature, not to mention native 16:9. -->>>

and the perfect colour balance.... though any defects of manufacture in hardware or software aren't covered by a warrantee of any sort!!

and how about updates? any news?

... and - on which version we are currently working?


and interested one - the software is region free - no PAL, SECAM or NTSC or different frequency rates...

who is the owner of the copyrights?


filip

I'm sure most everyone has seen the various round-n-round discussions that people get into about the equivalent pixel resolution of film. Well, the visual system is so much different than either film or video that those kind of debates would never be resolved (BTW, that's an optics pun).

The clarkvision article linked above does provide some interesting information, but goes too far in terms of equating visual acuities to pixel counts; some of those confounding points have already been mentioned, such as the super "pixel shift" of visual scanning and the very limited area of sharp central vision (just a couple of degrees wide). The old demo of that is to hold a pen at arm's length at fixate on one end. You cannot read the writing on the shaft of the pen just 5 or 6 cm away without diverting your gaze.

Standard Snellen eye charts are designed such that the 20/20 line represents a visual resolution of one arc-minute (the width of the lines in the letters is one arc-minute, so the "E" is 5 arc-minutes in total height -- 3 "arms," 2 spaces high). Some people can see as much as twice that sharp, 20/10, or resolving power down to 30 arc-minutes. If you accept that as optimum performance, you can determine an approximate pixel count for foveal (central) visual acuity.

Still there will be all kinds of caveats because of the complex way the human visual system works. For example, high contrast linear targets (like distant power lines) can often be resolved at much finer resolutions -- presumably a real neural pixel shift. Another interesting phenomenon is that although your peripheral vision is terrible in terms of resolution, it is exquisitely sensitive to motion; computer geek example: ever notice how you can see a CRT screen flicker in your peripheral vision, but when you look at it, the flicker disappears? And then there's the effects of retinal after-images, the "CPU" involved...etc, etc.

Anyway, I guess one could approximate an answer to the original question by calculating a pixel density for the sharp central 1.5 or 2 degrees of vision, based on pixels that are half an arc-minute in size. It might actually be more practical to convert an image of known pixel resolution, size, and distance from the eye into arc-minute resolution to get a comparison. That might even be useful for deciding how big of an HDTV you "need" for your family room! Either way, I'm too lazy to do the math this morning, though... ;-)

<<<- While it is quite sensitive to low light (basically the eye can count single photons) the aperture is rediculously small, making it quite inefficient at light gathering. The lenses are pretty low quality.-->>>

I rather retain the depth of field that our eyes possess, than have better night vision.

No images pixel count will ever convey more information than an eye can perceive - not to mention it's an analog system - so I would say the human eye has infinite pixels.

Analgoue != infinite

Does analogue video tape have infinte resolution - no, it's noise and bandwidth limited, as is analogue audio tape. Noise is very equivalent to digital bit depth, and bandwidth to resolution.

Also, the eye is made op of discrete light sensing cells, and if you count them, you'll get the resolution of the eye, although, as has been pointed out, the software that interperets these pixels is phenominal at perceiving more detail than there is sensed at the eyeball by integrating information over movement and time.

Graeme

But a human eye is not videotape. We're talking about the perception of actual light energy, which I think is essentially an infinite resolution spectrum.
Though I suppose one could define light by photons and show where there is actually a "digital" aspect to light energy.

My only point was that you will never be able to perceive more than your own eye, so for all intents and purposes it's infinite, imho.

Well, you can set up test cards, and keep moving them nearer until you can see the pixels so to speak, on the test card. Then you can use trigonometry to calculate the angles and distances and work to figure out the size of the eye's pixels.

Or as I say, you can get a microscope and count them - they're small, but not so small as to be invisible.

There's a world of difference between a large, finite number and an infinite number.

Just because you cannot percieve more than the limits of your own perception does not make your perception infinite.

Graeme

We're forgetting that no two moments of visual images captured by our brain are the same! Even in complete darkness we actually "see" too.

In addition, we have two eyes and each one is unique on how it translate light into images in our brain. It's very interesting!

<<<-- Originally posted by Graeme Nattress :
There's a world of difference between a large, finite number and an infinite number.

Just because you cannot percieve more than the limits of your own perception does not make your perception infinite.

Graeme -->>>

But if you cannot perceive the difference, is there a difference? :)


I understand the point that there is a limit to detail perception for each person.

I have not seen an 8K image projected, but I can imagine it would be perceptibly similar to 35mm for most people. Surely 35k imagery would be above and beyond requriements.

Online about a year ago somewhere I read this article about the Japanese...they created a super-HD camera. It was like 8k or something and they took it out and shot on the street while driving. They weaved through traffic and tried to give a real life like ride.

They projected it for people sitting in chairs in a room and they all started barfing! Apparently, the "motion" made them sick because their bodies weren't moving. That's going to be some really cool stuff when they figure out how to get it all together.

>>We're talking about the perception of actual light energy, which I think is essentially an infinite resolution spectrum. <<

GAH!!!! What the heck is a "resolution spectrum"?

As I've heard thus far (you never, know the profs could still be lying to me) space is NOT quantized... However, the quantum nature of light dictates the ultimate resolution of the visible spectrum. The resolution of light is limited by its wavelength/energy (related by Plank's constant), with visible light on the order of 100's of nm, and hence light can't accurately be used to resolve structures much smaller than 0.1 μm without incurring significant undersampling artifacts (otherwise known as diffraction).

I have no respect for the whole "if I can't see it, it doesn't matter" approach. We build cameras to be better than our eyes, so that our intrinsic frame of reference is not the limiting case in our perception of what's happened.

Think abot those spy cameras that can read license plates at 60k feet. Much better than the human eye.

<<<-- Originally posted by Steven White :
GAH!!!! What the heck is a "resolution spectrum"?-->>>

Answer:

<<<-- Originally posted by Steven White :
However, the quantum nature of light dictates the ultimate resolution of the visible spectrum.-->>>

So you're saying it's not infinite - fine with me.

<<<-- Originally posted by Steven White :
I have no respect for the whole "if I can't see it, it doesn't matter" approach. We build cameras to be better than our eyes, so that our intrinsic frame of reference is not the limiting case in our perception of what's happened. -->>>

But your visual perception is the limit of your visual frame of reference. If you had the ability to capture and display xrays, sure your camera is doing more than an eye is capable of perceiving, but you'd never know - unless you measured the xrays coming off of your screen.

But you wouldn't see them.

Plus, isn't the whole point of this thread to guess at what is the limit of perception?
The question being how much resolution is required to match what one can perceive?

If people literally cannot perceive more than 35k resolution image, what would be the point of making it 36k?

I would say, if one cannot perceive more than 35k, then it doesn't matter if the image is 36k.

<<<-- Originally posted by Joe Carney : Think abot those spy cameras that can read license plates at 60k feet. Much better than the human eye. -->>>

But that's the lens is it not?

If you could put your eye on the end of that lens, I bet you could read the license plate too - or am i thinking of the wrong thing?

>>I would say, if one cannot perceive more than 35k, then it doesn't matter if the image is 36k.<<

My argument is the following:

If I had a camera that could capture x-rays, I could translate that information into something my eye COULD see. That is in fact the whole point of medical x-rays, which are surely useful. My point is that while your eyes are limited, capturing information you can't perceive is possible. It is further possible to translate those into things you can perceive.

>>If people literally cannot perceive more than 35k resolution image, what would be the point of making it 36k?<<

The answer is that people cannot perceive a 35k image instantly... however, given enough time on a single image, we COULD process all the information. If we took a 36k image, eventually we could process that too. This is the point of something like the gigapixel project.

The point of increasing resolution is to add "depth" to the experience. The world around us is significantly more detailed than we can perceive, and I think we find comfort in knowing that if we looked harder, we could find out more. This is what's so great about IMAX and other large-format images... or photography in general.

I hold that one of the reasons people find CG frustrating is that they can tell there's nothing more there than what they've been shown. If they go closer, you'll see detours from reality and engineering hacks to the render... and once you've cracked that, there's no where left to go. Litterally an empty shell.

It all comes down to philosophy I guess.

Yes, it is very interesting. :)

I remember reading once, and I wish I knew the source, that a person with 20/20 can resolve approximately 1/60th of one degree of resolution. At 10 feet away, this would be 35/1000ths of an inch.

Now, we're told that the ideal picture size is 1/2 the viewing distance, right? The diagonal would be 60 inches, the horizontal would be 52" and the vertical would be 29".

So ideal viewing distance, and ideal 16x9 screen size. Let's make the pixels exactly as small as the human eye can see and no smaller.

52" / .0035" = 1490
29" / .0035" = 831

There you have it. A TV screen at ideal viewing distance needs to have 1490x831 resolution for the pixels to be invisible to the eye. As it happens, HDTV is 1920 x 1080 or 1280 x 720. So 720p and 1080i are slightly under what the eye would consider seamless, while 1080p is more than enough.

If we go the other way, and say how far should we sit from a certain TV set in order to have a seamless picture, that's easy.

For a screen width of 1920 pixels, take the screen width in inches, w. Pixel_size = w / 1920. tan(1/60 degrees) = pixel_size / viewing_distance. viewing_distance = pixel_size / .000291.

viewing_distance = (w / 1920) / .000291

viewing_distance = w / .56 = 1.8w

So for a 1080p display, multiply your screen width by 1.8 to get your ideal viewing distance.

For 720p, it's:

distance = w / (1280 * .000291)

viewing_distance = 2.7w

QED.

The thing is, the eye doesn't resolve images along a plane, the way either film or digital does. There aren't actually "pixels" in a 3D image.

@Peter Moore

So you'd need a 60" 1080p HD display 5' away to enjoy a perfect viewing experience!?
IT'D BE LIKE IMAX!!
lol!

oh guys you are talking about my fav subject, i'd written about this here @ Dvinfo way back, and also at extreme in depth @ dvxuser.com about the exact Long long chemical reactions ...

Anyway that aside i Just couldnt resist to ask the age old question:

"To whom does the eye inside belong?"


please visit this excellent site for more info about this topic
(read all the pages, you will love it!)

http://www.secretbeyondmatter.com/ourbrains/theworldinourbrains.html

v. interesting, but does it really matter? imho, 1920x1080p will do fine for consumers for a VERY VERY long time. even with the Japanese Ultra Defintion @8440x4440 it won't really matter cause it'll only be marginally better but at too much of an expense and space. most people don't have houses that can accomodate a '4k' image. cinemas can benefit but i think even '2k' is fine for the cinema (on the largest of screens). it's just that when you go beyond so much resolution it becomes meaningless... unless you need spy gear/satellite stuff. then you'll need it to be as high as possible.

i think somebody got the point with the word seamless.
first part is getting seamless pixels (so you can not see the discrete components of the picture, being pixels or dot on paper), so you can say that it is enough.
The second part is then to consider if we admit that it is enough to consider having this only in one direction, eyes focused on a screen) or covering all the field of vision.
the third part is not really really a pixel count, but rely more on the refresh rate (the pixel lifetime).
And the fourth part is counting it twice (we got two eyes) for depth perception.
Probably you have been already fooled by some demo of HD screen disguised in a window or fish tank, when seen at reasonable distance looking like real life until you convince yourself of the trick by gluing you nose on the screen.

<<<-- Originally posted by Christopher C. Murphy : Online about a year ago somewhere I read this article about the Japanese...they created a super-HD camera. It was like 8k or something and they took it out and shot on the street while driving. They weaved through traffic and tried to give a real life like ride.

They projected it for people sitting in chairs in a room and they all started barfing! Apparently, the "motion" made them sick because their bodies weren't moving. That's going to be some really cool stuff when they figure out how to get it all together. -->>>

Murph,

That barfing sensation has more to do with human sensory disagreement than the optical properties of the camera. If those people had closed their eyes, the sensation would have disappeared. It's a type of vertigo. The human ear has three rings mounted roughly vertical, horizontal, and a 45 degree angle. These rings are filled with fluid that comes in contact with small sensory hairs inside the ring. When you move or tilt your head fast enough to impart motion to the fluid in these rings, you perceive motion. That's all fine and good as long as the image your eyes see agrees with the movement of the fluid. However, when a pilot looks out the window and sees nothing but darkness or gray clouds, they will not perceive a slow movement in any direction because the fluid isn't disrupted. Without a moving horizon in the visual frame as a cross check, vertigo ensues. The reason you get dizzy when you stop spinning in a circle is because you have the fluid still moving while your eyes say you aren't anymore or if the fluid moves faster on one side of the head than the other. This is also how thrill rides at the amusement park work to make you dizzy.

I mentioned this because our senses work together and anytime there is diagreement, the brain gets confused and it cam lead to barfing (motion sickness), vertigo (not knowing which way is up or down, left or right), or both. It requires extensive training to make your brain disbelieve what your senses may be telling you using an alternate reference. In aviation, that's what an 'instrument rating' is for. Learning to trust the instruments and not what your body is saying. I could go on and on about how this knowledge is put to 'everyday use' like your example above, but I will save that for another time and/or forum.

All in all, a very interesting thread here.

regards,

-gb-

About 576 Megapixels

Now just divide that by 4 to find out the amount of reds, greens, and blues, and low-light cells in your eye if your brain could only process light, and nothing else. We have a blind spot and hearing and motor skills and all that processing power constantly being used up in our brains so the regular resolution of the human eye is around 6-8 megapixels per color and 2.2 megapixels (HD) in low-light. Plus, our eyes have way better exposure compensation (using section by section exposure control) than any HD camcorder. any type of film can do this but if someone can make a camcorder that could do intellegent section by section exposure, we will be one step closer to reality on physical memory (Tape, P2, and HDD). IMAX is the best example (although it's film) of virtual reality.

<<<-- Originally posted by Christopher C. Murphy : Online about a year ago somewhere I read this article about the Japanese...they created a super-HD camera. It was like 8k or something and they took it out and shot on the street while driving. They weaved through traffic and tried to give a real life like ride.

They projected it for people sitting in chairs in a room and they all started barfing! Apparently, the "motion" made them sick because their bodies weren't moving. That's going to be some really cool stuff when they figure out how to get it all together. -->>>

Murph,

That barfing sensation has more to do with human sensory disagreement than the optical properties of the camera. If those people had closed their eyes, the sensation would have disappeared. It's a type of vertigo. The human ear has three rings mounted roughly vertical, horizontal, and a 45 degree angle. These rings are filled with fluid that comes in contact with small sensory hairs inside the ring. When you move or tilt your head fast enough to impart motion to the fluid in these rings, you perceive motion. That's all fine and good as long as the image your eyes see agrees with the movement of the fluid. However, when a pilot looks out the window and sees nothing but darkness or gray clouds, they will not perceive a slow movement in any direction because the fluid isn't disrupted. Without a moving horizon in the visual frame as a cross check, vertigo ensues. The reason you get dizzy when you stop spinning in a circle is because you have the fluid still moving while your eyes say you aren't anymore or if the fluid moves faster on one side of the head than the other. This is also how thrill rides at the amusement park work to make you dizzy.

I mentioned this because our senses work together and anytime there is diagreement, the brain gets confused and it cam lead to barfing (motion sickness), vertigo (not knowing which way is up or down, left or right), or both. It requires extensive training to make your brain disbelieve what your senses may be telling you using an alternate reference. In aviation, that's what an 'instrument rating' is for. Learning to trust the instruments and not what your body is saying. I could go on and on about how this knowledge is put to 'everyday use' like your example above, but I will save that for another time and/or forum.

All in all, a very interesting thread here.

regards,

-gb-


What Murph is saying is that the resolution is so high, it easily "fools" the brain into interpreting the video as real, causing the miscommunication of sensory data and the subsequent queesy effect.