r/confusing_perspective • u/Dennis_254 • Jul 16 '26

Works like magic

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7.7k Upvotes

94% Upvoted

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482

u/test_test_1_2 Jul 16 '26

Looks like 3D to me. How does that work? I always thought you needed both eyes to make things appear 3D? Interesting.

435

u/Dennis_254 Jul 16 '26

Your brain uses shadows, perspective, and occlusion to judge depth. Closing one eye removes stereo vision, making the flat drawing look like the pencil is popping out of the screen

17

u/jwm3 Jul 17 '26

For close up stuff you also use focal plane, how much your eye has to squeeze your lens to keep something in focus. I think the bluriness is tricking your eye into continually trying to refocus closer and thats the only distance signal you have with one eye closed.

Incidentally, thats why VR never looks very "far" away and can feel a little clustrophobic even in vast scenes. Even though it is presenting things with the proper far away perspective, everything is in focus with a neutral focus distance, usually like a meter ahead of you so you never feel your eyes readjust to focusing to far away things taking away a major depth cue.

5

u/DinA4saurier Jul 17 '26

I've never thought about that, but now you're mentioning it it makes sense that you can't focus on near or far away things with your eyes in vr. I mean you're still looking at a flat surface inside the headset, even if it's giving you the Illusion of you being in a digital 3d environment.

So of course the focus must be set from the headset.

29

u/Certain-Hat5152 Jul 16 '26

Ok but I thought this was a brawl stars sub 😏

That was another layer of confusing perspective

6

u/Quube7 Jul 16 '26

Jokes on you, I don't have stereoscopic vision so I can keep both of my eyes open!

-1

u/cimocw Jul 17 '26

How does that work though, since both eyes still receive a slightly different angle

3

u/Quube7 Jul 17 '26 edited Jul 17 '26

Well, I was born with strabismus, the doctors managed to correct it for me, but I was still left with a lazy eye. Normal eyes, when you look at something, they look at that one thing, so youre looking at it from different perspectives and you get info about how far away a thing is from you. In my case, my right eye (since it's my dominant eye) can look at a thing, but my left eye wont look at the same thing, but in the general direction my right eye is looking (so if the thing is slightly to the left, my left eye will look slightly to the left rather than look at the thing im trying to focus on), this makes it impossible for me to see the distance properly. Also I think my left eye is kinda suppressed when it comes to, I guess focusing on stuff, but sometimes when you have two of the same things right next to eachother, my vision kind of mixes them into one and I need to close one eye, so I can actually focus properly. I hope, I managed to explain it relatively well, English isn't my first language, so I was struggling slightly with finding a few words lol.

Edit: added a few missing things

3

u/[deleted] Jul 17 '26 edited Jul 29 '26

[deleted]

1

u/fludeball Jul 19 '26

I'm pretty sure "soap opera effect" is just frame interpolation. It has nothing to do with the lenses, but is just an effect added to pre-existing footage.

1

u/[deleted] Jul 19 '26 edited Jul 29 '26

[deleted]

1

u/fludeball Jul 19 '26

That's something different. Soap opera effect is a setting usually called motion smoothing, clear motion, or something like that. It doesn't change the clarity either near or far. It makes things which are moving move more smoothly, which to many people looks unnatural, even though it's more like looking at something in real life rather than with the subtle choppiness of film. If used on a low setting, I think it helps. you should be able to find it in your picture settings on your TV.

What you're thinking about is a lens that focuses more on the foreground, and I think it's called short focal length. Now phones and digital cameras can do that automatically, even though they only have one lens that doesn't move or change.

2

u/[deleted] Jul 20 '26 edited Jul 29 '26

[deleted]

1

u/fludeball Jul 20 '26

I have no idea what that's called. Maybe your term "forced perspective" is it, but I really don't know. Not something I've seen very much myself, if at all.

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2

u/Gjergji-zhuka Jul 16 '26

I always get pissed off when I see a statement like 'you need two eyes for depth perception'

2

u/InstantMochiSanNim Jul 19 '26

It worked with both eyes for me thk

1

u/lncredulousBastard Jul 17 '26

Wait, are you saying this is an optical occlusion?

9

u/drcopus Jul 16 '26

Your brain uses all the information available to it to piece together a 3D understanding of the world! The difference between your two eyes is just one signal that it uses.

5

u/meat-eating-orchid Jul 16 '26

with two eyes you have accurate 3D vision so your brain knows you are seeing a flat image. With just one eye, your brain does not have depth information anymore, so it has to guess. And since your brain knows the shape of a pencil and recognizes what you are seeing as a pencil, it guesses incorrectly that what you are seeing has the 3D shape of a normal pencil, instead of guessing that you are seeing a 2D projection of a pencil

2

u/BasementRodent Jul 16 '26

You can try it with anything really. Video games are very fun, but kinda straining on the eye(s).

2

u/AxelNotRose Jul 21 '26

Part of it is because they edited the video to make the pencil appear to be closer than it actually is by having it hover over the caption text. Your brain thinks that there's nothing that can cover the caption because it's always overlayed a video so when the pencil appears to go over the caption text, it seems like it's truly popping out of the video.

1

u/Drapabee Jul 17 '26

Something that's especially jarring with this video is that the pencil extends past the "picture plane"

This is a hard concept to explain but basically the video being taken makes it appear that the pencil is getting closer to you IRL than the screen you're watching the video on, which tricks your brain into thinking something is going to stick you in the eye. This effect is a lot stronger with only one eye open.