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> Consider foveation as well — only a small part of that is truly in “focus”.

Here's an optical illusion which illustrates how surprisingly tiny your fovea's FOV is: https://www.shadertoy.com/view/4dsXzM .



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Here's an optical illusion to show how small your fovea's FoV is: https://www.shadertoy.com/view/4dsXzM

> FOV is a problem that lenses simply can't solve

Would you or someone else mind elaborating on this? I am unfamiliar with this problem.


> The human field of view is actually about 4:3.

I believe it's more like 2:1 (so even 16:9 isn't quite wide enough).


> It must be a trip to have an entire field of view in focus all at the same time.

I'm not sure that this is possible. Even if the lens system allows it, your retina isn't.

http://en.wikipedia.org/wiki/Fovea


> After all, our eye really is at different distances from different parts of a straight wall, so it sounds logical that we would see the fisheye effect describe in the article.

It's not the distance to the points in the scene that determine where they appear in a perspective projection, it's the angle. For any single point on the screen/retina/projective plane, it can actually correspond to any distance from the camera/eye (i.e., a ray of possible points).


> Depth of field is a human eyes thing too.

Not in in the dumb way games do it: You don't need to turn your entire head to make something come into focus, or aim it with with a gun.


That's the size that is relevant to foveated rendering. But note that your actual physical fovea is even smaller than this, due to saccades.

>Really? You can’t set up more than one monitor in your field of view? &

Just because we can see movement on the outer ends of our field of view to see predators, doesn't mean I can also comfortably stare at code via the side of my eyes. Filed of focus != field of view. Yeah, I can see nearly 180 degrees, but I can only comfortably focus for work on what's in the center of my FoV.


>No, this is wrong. Your eyes can't detect the difference between 4k and 8k at routine (i.e. 90 degree width or so) distances. They just can't.

proof please.


>are tricked into variably focusing based on simulated depth

No, the focal distance in a headset is fixed. The light hitting your eye is always coming in at the same angle.


> In front of the imaging devices there are high speed mask device (LCD?) that blocks off portions of the image that are not at the current focal depth.

It would be interesting to see how this works in practice. The eye can't focus on something that close. For an example, imagine a speck of dirt on your glasses - it shows up as a blob in your vision, not as a dot.


> but the focal length afforded by the lenses is fixed

That seems weird to me because when I look at a screen at a different distance to the one I'm using I can see the other screens getting blurry just like in real life.


> The FOV is 95° at a pupil distance of about 8mm and 90° at a pupil distance of 12mm.

Meh, pass. The Index is at 130 degrees and even that looks like you're looking through a pair of toilet paper rolls.

Why do they bother going with such high resolution if they don't expand the FoV? It's just gonna chug more with your average mid range graphics card.


> eyes have really high resolution

That's not actually the case, from what I heard. Most of our peripheral vision is smudged 720p at best, and we can only see a tiny focused area at slightly beyond 4K density. We also can't look at two things at once.

The dynamic range part is definitely true though.


> that's why we have a pair of eyes and not a single eye.

This is really overstated. It really only matters for about 3 or 4 meters of distance. We do depth perception well enough at distances to drive cars.

We also do just fine at perceiving depth in video games and single lens camera.

How often do you have trouble determining the depth of something in a movie? Only about as often as the filmmakers want you to.


>But the input to the visual system is still an image on your retina, which obeys the same laws as camera optics.

The thing that makes the difference is that the resolution of the retina drops as you move off the center. Which I suppose is what is being simulated here. Or at least it could be efficiently simulated that way - like foveated rendering, only the fovea is kept at the center and the rest of the image is kept with the pixels smashed closer together instead of interpolated.


Consider foveation as well — only a small part of that is truly in “focus”.

Some up and coming be glasses take this into account and expend lesser resources on the part that’s outside the important part (they don’t render that part in a high resolution, so it’s left blurry, which is actually how our eyes work anyway)


The article barely mentions foveated rendering, in the middle of a sea of "use your gaze to click it'll be great I promise".

> we're talking apparent pixel density which is directly related to screen distance.

If you ignore all the glass/plastic between the screen and your eye that's required to focus on it.

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