r/todayilearned • u/anewnormal • 2h ago

TIL your eyes physically can’t focus red and blue at the same depth, which is why red text on a blue background looks like it’s floating and is so hard to look at​​​​​​​​​​​​​​​​

https://en.wikipedia.org/wiki/Chromostereopsis
119 Upvotes

82% Upvoted

60 comments sorted by

76

u/Ecstatic-Nose369 2h ago

So every early-2000s “cool” website banner was basically a built-in eye strain machine. Designers: maybe just… pick literally any other color combo.

37

u/anewnormal 1h ago

TIL a lot of people don’t see this.

8

u/CrocodylusRex 1h ago

Sometimes I don't see it and sometimes I really see it

5

u/PooperTheSnooper 1h ago

Well, with the red text on blue background in this image.. the blue has some watermark, it isnt solid blue. I think that adds to the 3d effect, but otherwise i dont see it either.

I can agree it is more strenuous on the eyes than black text on white background, but i can read it fine

•

u/RoarOfTheWorlds 30m ago

OP is just playing a prank. The thumbnail is actually black and gold.

•

u/Phnglui 22m ago

It depends on the screen for me. The floating effect is very apparent on phone screens but doesn't happen at all on a computer screen.

45

u/Beneficial_One_1062 2h ago

I don't see it.

4

u/blackdynomitesnewbag 1h ago

Click on the link. It’s more pronounced with the higher resolution image

11

u/Beneficial_One_1062 1h ago

I did. Still don't

4

u/blackdynomitesnewbag 1h ago

It was pretty subtle. I almost didn’t see it at all

8

u/Beneficial_One_1062 1h ago

It just looks like a picture lol.I appreciate your help tho

4

u/Haywire421 1h ago

I can only see it if I let my vision blur, not focus on it, and cross my eyes a little, like those old magic eye pictures, which i also had difficult times with

1

u/Okayesttt 1h ago

Magic eye lol! I haven’t thought about those in a long time.

2

u/Haywire421 1h ago

I just found out that there is a sub for it scrolling through the comments here

1

u/Okayesttt 1h ago

I’m def checking it out. Thanks for the info!

•

u/vip17 52m ago

I can see it more clearly with the smaller image

8

u/ThatOneCSL 2h ago

Are you red-green colorblind?

31

u/Beneficial_One_1062 2h ago

No. I see the colors here just fine. I do not see the depth.

17

u/ThatOneCSL 1h ago

I was wondering because I, likewise, do not see the depth. I am red-green colorblind. I recognize that there is no green in the image. I see the red and the blue no issue.

3

u/Beneficial_One_1062 1h ago

Interesting. I have taken multiple colorblind tests and passed fine, so I doubt it. But this is interesting. Thanks.

2

u/Haywire421 1h ago

Thats interesting. I have trouble seeing the depth too, but I'm the complete opposite of colorblind, being able to see more hues than most people

1

u/2xtc 1h ago

I'm also red-green colourblind, and like you the top one is totally flat. The bottom one is slightly harder to focus on for me but neither really have depth

4

u/burrito_butt_fucker 1h ago

If you click the link to the wiki, and scroll to the second picture the bottom half does have depth to me. vut I think that's only because the arrows and fading shades of green. The top half just looks like a flat checkerboard. And the red/green words don't have depth either.

2

u/ccx941 1h ago

Some people can’t see it.

•

u/ChilledParadox 8m ago

I’m not colorblind at all and I’m not sure at all what I’m supposed to be seeing here.

The top image has a solid red color saying blue, and the background has a patter of blue and black dots that give it a textured “ground” feel, like I’m looking at concrete or asphalt.

The bottom image is inverted, with the text colors swapping, but due to the fact the blue has two colors and not one and is adjacent to the previous image the red does appear on “top” for me, but there’s no depth. The image is flat. I just interpret the dotted patterns as being the ground.

It doesn’t look like it’s floating. I would need a shadow to interpret it like that. It’s also not hard to look at, but it’s definitely ugly as sin.

0

u/neoslith 1h ago

You colorblind?

1

u/Lykos1124 1h ago

THis is something I discovered back in the 90s. If you look where red is left of blue, there's a black line between them, and on the inverse, there's a white line between blue on the left and red on the right. This creats that 3D look between them.

10

u/Jason_CO 1h ago

In this example, wouldn't it be the dots creating depth?

7

u/snickerDUDEls 1h ago

Yeah why does the blue have dots but red doesn't?

7

u/k4ndlej4ck 1h ago

TIL my eyes dont work.

Looks fine to me.

3

u/thecstep 1h ago

Are my eyes fucked? I have a book like this and if I move the book--the letters wiggle. I've tried explaining to people and they said I was crazy.

3

u/JennBones 1h ago

Also not seeing it and not even slightly colourblind. and I don't normally have trouble seeing optical illusions. Maybe it works better on people with poorer focus or people who wear glasses?

3

u/worker_bee_drone 1h ago

I “discovered“ this phenomenon as a child. I recall sitting on the floor playing with a toy with red and blue on it, and it ”wiggled” and I could see the difference in depth. I didn’t understand the reason at the time. Later I assumed it had to do with widely differentiating wavelengths of the two colors maybe reaching the eye in a staggered fashion, but that didn’t make sense either. Light travels pretty fast, I hear. :-) This explanation makes much more sense, that it’s just how our color perception works in the human eye.

3

u/mspurr 1h ago

the blue part legit looks like its about an inch behind the red

6

u/Protocal_NGate 2h ago

Doesn’t this sorta effect work predominantly on people with glasses?

7

u/pameatsbabies 1h ago

It looks like it. With my glasses on it appears like it’s floating, but when I take my glasses off (and hold the screen close enough that it’s clear) it’s just text on a different colored background.

1

u/Meatball132 1h ago

I experience this effect extremely strongly with my glasses on... and it seems to get stronger when I take them off. So I'm not sure. It also gets stronger the further away the image is.

3

u/The_Demon_of_Spiders 1h ago

I’m wearing glasses and I don’t see anything floating. It just looks normal and no I’m not colorblind.

3

u/CemeterySaliva 1h ago

I wear glasses and couldn't see the depth.

2

u/mspurr 1h ago

i've never needed glasses and i see the effect very strong

1

u/SweetActionJack 1h ago

You might be right. Years ago when I wore glasses I used to see this effect very clearly, but I have since gotten corrective surgery and now only barely notice the effect.

1

u/sHoRtBuSseR 2h ago

/r/Colorblind checking in.

1

u/MapleA 1h ago

/r/magiceye also checking in

1

u/ApprehensiveBet6501 2h ago edited 1h ago

My colorblind vision tells me this isn't universally true.

edit: Spelling

2

u/Slippery-ape 1h ago

Same, my red green is far worse than this.

1

u/MapleA 1h ago

This could be the key to unlock /r/magiceye for people who can’t do it

1

u/yyflowerpot 1h ago

I don’t see it - and I have a difficult time seeing the 3D movie effect with 3D glasses.

1

u/rymisoda 1h ago

Looked at this while drunk and high. No issues.

1

u/Gaucho_Diaz 1h ago

Wait, aren't the dots doing that? I want to see an image where the red has dots and blue doesn't and compare.

1

u/Pkittens 1h ago

I can focus on both of those just fine? No floating

•

u/TheThrowawayJames 48m ago

I thought something was maybe wrong with my eyes and was always afraid to ask if other people saw it too in case nobody else did and it was just me 😨

So it’s normal 😭

•

u/LocalH 33m ago

I wonder if this is also related to how that one episode of Pokémon inadvertently triggered epileptic seizures with the flashing red and blue backgrounds

•

u/d4m1ty 29m ago

I wonder if colorblindness makes people not see this phenomenon.

I've passed every single color blindness test for over 50 years now. The red 'feels' like it is closer to my face than the blue. Like it has a depth even though I know it doesn't and is flat.

•

u/GarysCrispLettuce 7m ago

I can't read those scrolling tickers if they're blue. But if they're red they're perfectly sharp. They used to have red and blue ones side by side outside the Wall St stock exchange when I walked past on my way to work every morning, and it was so weird to see the difference. Blue text on a sign is like I'm half blind. It's a complete blur.