nothing to fix The sensation of speed

[freehand]

Going to a bike rally riding my bike I was using a car satnav and because the device was on my tank bag the screen vibrated & the screen turned upside down I navigated four roundabouts but could not stand it any longer and pulled over hope this helps   

[Hiob]

29 minutes ago, average_pilot said:

If you mean how this eye convergence thing I explained before work for the size of the objects in the vertical dimension then I only have speculation. (Damn! I shouldn't have used a building as an example! :D)

 

Your answers to things I mostly already knew get longer and longer  - and I don't even disagree with most of it.

But the answer to my actual main question is this basically "I don't know"!  (Which is fine, we're already two)

That leaves my other question. What does a one-eye 2D-Mirror show, when the IDP/Worldscale in DCS is changed?

[draconus]

1 hour ago, Hiob said:

How does that work in the vertical?

In VR it simply doesn't work. If you can reproduce the image of the perfect horizontal lines at different distances there will be no difference in images for each eye, hence no depth perception. Very rare or impossible case though. Light tilt of the head or any single detail will bring the depth preception back.

[Hiob]

2 minutes ago, draconus said:

In VR it simply doesn't work. If you can reproduce the image of the perfect horizontal lines at different distances there will be no difference in images for each eye, hence no depth perception. Very rare or impossible case though. Light tilt of the head or any single detail will bring the depth preception back.

You missunderstood me. I was referring to average_pilots claim, that a change in IDP (aka the horizontal distance between the cameras) causes the change in world scale - and I asked how does a horizontal change in IPD makes objects larger in the vertical dimension.

Edited March 4, 2024 by Hiob

[SharpeXB]

19 minutes ago, Hiob said:

You missunderstood me. I was referring to average_pilots claim, that a change in IDP (aka the horizontal distance between the cameras) causes the change in world scale - and I asked how does a horizontal change in IPD makes objects larger in the vertical dimension.

 

Well since the world scale is the world. Objects would get larger and taller corespondingly in any dimension. It’s best not to overthink it

[draconus]

5 minutes ago, Hiob said:

What does a one-eye 2D-Mirror show, when the IDP/Worldscale in DCS is changed?

The bigger IPD the more camera shift from the center of default view point - that's all.

2 minutes ago, Hiob said:

You missunderstood me. I was referring to average_pilots claim, that a change in IDP (aka the horizontal distance between the cameras) causes the change in world scale - and I asked how does a horizontal change in IPD makes objects larger in the vertical dimension.

Since depth perception is created in the brain with our own IPD any image presented with different IPD will spoil the world scale for us (assuming the game has real life size objects in the first place). No dimensions (both vertical or horizontal) are really changed. It's only illusion - that's why you can't show it on the screenshots.

[Hiob]

25 minutes ago, SharpeXB said:

It’s best not to overthink it

Right. But since people are making rather bold claims from my pov - I'd liked to have them backed up with some actual explanations. So far the best explanation was "...and then you're brain figures it out" (boiled down).

To me that's too vague, sorry.

To get it straight: I don't claim to know how it works and I am really interested to learn some actual facts. But the one thing I do know is, brain adaption isn't instant. That's why all those lengthy explanations sound so fishy to me.....

[Hiob]

56 minutes ago, draconus said:

Since depth perception is created in the brain with our own IPD any image presented with different IPD will spoil the world scale for us (assuming the game has real life size objects in the first place). No dimensions (both vertical or horizontal) are really changed. It's only illusion - that's why you can't show it on the screenshots.

When the 2D-Mirror doesn't change (except for a side shift), that would support the idea, that in-game IPD alone is responsible for the change of perceived scale. But has anyone actually checked that?

Your answer present it as a given, that a horizontal change in IPD somehow affects both horizontal and vertical perception in game. That was my question: how and why is that?

And no - the brain doesn't make a flat rectangle into a perfect square - at least not instantaneous.

EDIT: Took some edges off, shouldn't sound so hard..... 

Edited March 4, 2024 by Hiob

[SharpeXB]

1 hour ago, Hiob said:

and then you're brain figures it out

Well that is in fact the answer. Your brain interprets your stereo vision. But that’s only part of it. A lot of depth perception is learned. There’s also the parallax shift when your viewpoint changes. 

2 hours ago, Hiob said:

how does a horizontal change in IPD makes objects larger in the vertical dimension.

Because when something is taller vertically it’s also farther away. There’s no way to separate the horizontal from the vertical. 

[Hiob]

16 minutes ago, SharpeXB said:

Well that is in fact the answer. Your brain interprets your stereo vision. But that’s only part of it. A lot of depth perception is learned. There’s also the parallax shift when your viewpoint changes. 

Again, I didn't ask about depth perception.

17 minutes ago, SharpeXB said:

Because when something is taller vertically it’s also farther away. 

What

17 minutes ago, SharpeXB said:

There’s no way to separate the horizontal from the vertical. 

That's not how physics usually works. X and Y are two very distinct dimensions ans you are only adjusting one of them. 

Nothing but claims - no explanation. 

[SharpeXB]

1 minute ago, Hiob said:

That's not how physics usually works. X and Y are two very distinct dimensions ans you are only adjusting one of them.

This isn’t physics. It’s 3D space. You can’t separate one dimension from the other. That should be fundamentally obvious. 

[Hiob]

Just now, SharpeXB said:

This isn’t physics. 

Then it's metaphysics? 

[SharpeXB]

1 minute ago, Hiob said:

Then it's metaphysics? 

No it’s such a simple concept it’s hard to explain. You’re asking why changing the distance between your virtual eyes in VR affects the vertical size of something? The answer is so obvious it shouldn’t need explaining. 

[Tippis]

Of course, one of the most extreme sensations of speed come from when that speed makes your four dimensions expand at different rates…

[RealDCSpilot]

22 minutes ago, Hiob said:

Then it's metaphysics?

Why all the fancy dancing around the matter? In VR options you can force IPD. Simply try 40mm vs 80 mm and check what happens. (Hint: one will transform you in a toddler and the other one into a giant.)

[Hiob]

1 hour ago, SharpeXB said:

No it’s such a simple concept it’s hard to explain. <…> The answer is so obvious it shouldn’t need explaining. 

1 hour ago, RealDCSpilot said:

Why all the fancy dancing around the matter? In VR options you can force IPD. Simply try 40mm vs 80 mm and check what happens. (Hint: one will transform you in a toddler and the other one into a giant.)

Nobody denied that. I just wanted an explanation why. And when it really only is IPD, than I‘d love to know how exactly that works.

But all I get is: „Duh, it‘s obvious - don’t ask stupid questions!“

[SharpeXB]

24 minutes ago, Hiob said:

I just wanted an explanation why

Moving your eyes farther apart would change your perception of three dimensions. The distance between your eyes, known as **binocular disparity**, is crucial for depth perception. This disparity allows your brain to compute the depth of objects by comparing the slightly different images each eye sees. If your eyes were farther apart, the disparity would increase, potentially enhancing your ability to perceive depth at greater distances¹².

However, it's important to note that human vision relies on a complex interplay of multiple cues for depth perception, not just binocular disparity. Other factors such as motion parallax, texture gradients, and occlusion also contribute to our three-dimensional vision². So, while increasing the distance between your eyes might alter your depth perception, it wouldn't necessarily improve it across all situations and might even make it harder for your brain to fuse the two images into a single 3D image¹.

Source: Conversation with Bing, 3/4/2024
(1) Stereoscopy - Wikipedia. https://en.wikipedia.org/wiki/Stereoscopy.
(2) Depth perception - Wikipedia. https://en.wikipedia.org/wiki/Depth_perception.
(3) Human eye - The perception of depth | Britannica. https://www.britannica.com/science/human-eye/The-perception-of-depth.
(4) Depth Perception: How Are We Able To See In 3D? - All About Vision. https://www.allaboutvision.com/eye-care/eye-anatomy/depth-perception/.

Edited March 4, 2024 by SharpeXB

[Tippis]

2 hours ago, Hiob said:

Nobody denied that. I just wanted an explanation why. And when it really only is IPD, than I‘d love to know how exactly that works.

But all I get is: „Duh, it‘s obvious - don’t ask stupid questions!“

Because the in-game IPD is fixed. Your virtual pilot's eyes sit a specific distance apart.

When you alter the player's IPD — because different players have differently shaped heads — you create a scaling factor between that in-game and out-of-game eye distance. To not make the world 3D-anamorphic, which would look very odd, that scaling factor needs to be applied equally to all axes. Thus, the whole world scales up or down to make sure it conforms to how it is supposed to look through that pilot's eyes.

It has nothing to do with depth perception. It has to do with linear scale and how it needs to be applied equally in every direction to not make the world go squish. This may create an effect where the world looks too large or small to you, because you are larger or smaller than the in-game pilot and aren't used to seeing the world around you through their… physique. If the game is fancy, you can also alter the in-game IPD, to reset the world to your expectations, but that just moves that one-dimensional scaling factor up or down, and it still needs to be applied equally to all axes.

 

edit #678: oh, and of course, there's also the issue of camera position over ground compared to where you expect your eye line to be, and how proportional the in-game character-height-to-character-IPD is in relation to your own proportions. If you've ever played around in Google Earth VR and flipped the switch between “always stand on the ground” vs. “always stay actual size” options, this is the relationship you're fiddling with.

Edited March 4, 2024 by Tippis

[draconus]

10 hours ago, Tippis said:

If the game is fancy, you can also alter the in-game IPD, to reset the world to your expectations, but that just moves that one-dimensional scaling factor up or down, and it still needs to be applied equally to all axes.

The thing is the game just moves the two viewpoints apart at the IPD value. No different scaling is applied, otherwise it could be seen in one eye view or the screenshots. Scaling happens inside the brain. If your RL IPD is 68 and you set it to 60 in DCS, you'll notice the scale is not right for you. Hand the headset over to your pal witch has RL IPD of 60 and he'll say it looks about right.

[RealDCSpilot]

@Hiob I don't really get why we have to explain this to you. Why are you not doing something simple as typing "Größenwahrnehmung und Augenabstand" in your search engine?

[Hiob]

2 hours ago, RealDCSpilot said:

@Hiob I don't really get why we have to explain this to you. Why are you not doing something simple as typing "Größenwahrnehmung und Augenabstand" in your search engine?

Simple. You don't have to when you don't want to. Nobody is forcing you to engage in this conversation. It is a question that came up with this topic, and I found the explanation for one certain (but important) detail lacking, I asked if someone could explain it to me.

Sure I can research it myself, but since some of the other guys seem so sure and confident about it, I figured someone could give a good explanation.

Sorry, if I appear dense - but for me it is was not so obvious, that a change in a horizontal dimension should affect the perception in a vertical.

 

Edited March 5, 2024 by Hiob

[Hiob]

15 hours ago, SharpeXB said:

Moving your eyes farther apart would change your perception of three dimensions. The distance between your eyes, known as **binocular disparity**, is crucial for depth perception. This disparity allows your brain to compute the depth of objects by comparing the slightly different images each eye sees. If your eyes were farther apart, the disparity would increase, potentially enhancing your ability to perceive depth at greater distances¹².

However, it's important to note that human vision relies on a complex interplay of multiple cues for depth perception, not just binocular disparity. Other factors such as motion parallax, texture gradients, and occlusion also contribute to our three-dimensional vision². So, while increasing the distance between your eyes might alter your depth perception, it wouldn't necessarily improve it across all situations and might even make it harder for your brain to fuse the two images into a single 3D image¹.

Source: Conversation with Bing, 3/4/2024
(1) Stereoscopy - Wikipedia. https://en.wikipedia.org/wiki/Stereoscopy.
(2) Depth perception - Wikipedia. https://en.wikipedia.org/wiki/Depth_perception.
(3) Human eye - The perception of depth | Britannica. https://www.britannica.com/science/human-eye/The-perception-of-depth.
(4) Depth Perception: How Are We Able To See In 3D? - All About Vision. https://www.allaboutvision.com/eye-care/eye-anatomy/depth-perception/.

 

 Depth perception wasn't in question, but how it affects the vertical size of objects.

However - I think I found the missing link in one of the articles you linked. "Aparent View Angle". (Note that we're talking the vertical angle here)

This is how I understand it now: The (vertical) size of objects on the displays doesn't change (we established that, thanks), but due to the fact that a smaller IPD makes them further away (depth perception), the apparent(!) vertical view angle is smaller. I hope I could put it in words properly.

Thanks guys for the patience!

[Tippis]

6 hours ago, draconus said:

The thing is the game just moves the two viewpoints apart at the IPD value. No different scaling is applied, otherwise it could be seen in one eye view or the screenshots. Scaling happens inside the brain. If your RL IPD is 68 and you set it to 60 in DCS, you'll notice the scale is not right for you. Hand the headset over to your pal witch has RL IPD of 60 and he'll say it looks about right.

Right. I was semi-purposefully vague there: it's not that the rendering is scaled but more that the instant you have a translation from one linear distance to another, all other dimensions have forcibly have to have the same translation applied to them or the world would go wonky in new and interesting ways. Exactly what parameters go into that translation can then vary depending on the game (and headset).

[MAXsenna]

 Depth perception wasn't in question, but how it affects the vertical size of objects.
However - I think I found the missing link in one of the articles you linked. "Aparent View Angle". (Note that we're talking the vertical angle here)
This is how I understand it now: The (vertical) size of objects on the displays doesn't change (we established that, thanks), but due to the fact that a smaller IPD makes them further away (depth perception), the apparent(!) vertical view angle is smaller. I hope I could put it in words properly.
Thanks guys for the patience!

Thank you for asking. I learned something too today!

Sent from my SM-A536B using Tapatalk

[average_pilot]

On 3/5/2024 at 11:48 AM, Hiob said:

 Depth perception wasn't in question, but how it affects the vertical size of objects.

However - I think I found the missing link in one of the articles you linked. "Aparent View Angle". (Note that we're talking the vertical angle here)

This is how I understand it now: The (vertical) size of objects on the displays doesn't change (we established that, thanks), but due to the fact that a smaller IPD makes them further away (depth perception), the apparent(!) vertical view angle is smaller. I hope I could put it in words properly.

Thanks guys for the patience!

The bare essence of stereo vision: the convergence angle that the eyes need in order to focus on different objects at different distances from the viewer, so that the left and right images of the object merge into one. There isn't much else about it.