Cursed wretched marketing

Red is complimentary to cyan.
If the cyan were switched with yellow, the can would appear blue.
Also, it's not our brains creating the red, it's our eyes. They get exhausted of seeing the cyan and replace it with red.
- Can you do that and post it?
  
  Checkmate, atheists.
- He's right.
  
  You guys never cease to amaze me.
- Huh, it shows up as black to me.
  
  It depends on the size you are viewing it at. This works well on small screens but less well on large screens
- so it would appear red even if it was another can?
- It's curious that the thumbnail actually has red values for those pixels, making me think they're cheating a bit with jpeg compression effects.
- So if the can shown wasn't Coke, but Sprite, it would still appear red? Or is it a mix of both? The eyes are confused and the brain fills in? Like when seeing pink as mentioned elsewhere.

It's not marketing, just colour theory. The same idea has been used by painters for ages.
- It is when you use cova cola instead of, lolipop, santa, flag, flower or some other red object.
  
  Here's another example
  
  Nah, it's still colour theory. Now it's yellow, magic.
- Its the second Coca Cola TM post ive seen since I joined lemmy.
  The other one was yesterday.
  
  This site has no protection against marketing aside from moderator action (and in this case OP is a mod). I'm not certain OP chose a coke can for that image or whether this was simply the first version of that illusion that OP has seen
  I wonder if prolific posters are approached by advertisers. Is Lemmy big enough for them to bother?

Nonsense. My phone screen uses red, green, and blue to make up each pixel. The white pixels have their red component all the way at full brightness. Therefore there is a lot of red in the picture.
You could also see this by opening up the image and looking at the red channel which would not be completely black.
- Texts on computers is made this way, so use a magnifying glass on black white text in a word document (for example) and you'll see lots of colors. zoom in using the computer and you will still just see black/white.
  
  So that's why I can't print greyscale documents when my yellow ink is too low!
- I just tried printing this image but it says my magenta is too low 🤔

Oh weird, I assume this is just because the white is relatively red compared to the cyan, right? As in if you took any image and coloured it in the same way then it would also look red.
- Yeah, there seems to be a lot more going on here than just marketing. If you mask the logo, the red still works. I believe it has to do with the combinations of white/black, white/cyan, black/cyan and the relative size of the blocks to produce a red hue through complimentary color persistence or whatever it's called.
- Hand doesn't look red tho
  
  The hand has cyan in it
  
  Brain uses expectations to decide what to fill perception with. you don't expect hands to be the same red tone as cola cans.

Jokes on you, I'm moderately red green colorblind so I wouldn't realize it if there was red present
- Do you see the Coke can as a different color from the background?
  
  I'm red green colorblind as well. I just see the background as white or a very light shade of grey. Someone else has made a post with a yellow can and in that one I see the background as yellow (which is basically the same as green to me, I have very little r in my rgb), especially the right side of the can.
- Same here. Those colour fanatics are fantasising again I suppose.

I think there's something more going on here than just "marketing". Because if you look at the tiny thumbnail in the OP it's very clearly red, and you can even load that thumbnail into an image editor and zoom in to see slightly reddish pixels.
So something happens when scaling this image that actually results in a red hue, and I don't think my computers image scaling algorithms are also falling for "marketing". I would guess it's actually some kind of sub-pixel trick that makes it seem like there's colors there which aren't, and that's why the image scaling algorithms also reveal the same colors you see.

Your mind compensates for the teal which makes the white look red.
- It makes gray look red because it's similar luminosity. White still looks white.
- The image has teal-black parts and white-black parts, the white-black parts look like they're red-black

That's wild as fuck. If I actually concentrate on the "red" it becomes white and then only becomes red again if I look away for a moment.

She's right.
- Damn i thought it was a shitpost at first

When its small thumbnail I can see it but when I look at the full size image I appear to be able to turn the effect off at will.
- If I zoom in just a bit it's white, turns instantly red at some point of zooming out.
  
  The tipping point is wild

Still red with no logo.
- White light has red in it. Cyan does not. We fatigue blue and green cones everywhere but the white can, and we only stimulate the red cones on the white can. The result is it looks red.
- Thank you. I thought this was going to be like the dress.
  
  The white and gold dress, you mean?

I'm colorblind this trick doesn't work with me

It’s actually all just white light at different wavelengths, which tricks your brain into seeing different “colours”.
- White light is the combination of all those wavelengths. It is only the combination that makes it "white" in exactly the same way that a smaller range of wavelengths are "red" or "blue".
- Making your brain do exactly what it's supposed to do is a weird way is "tricking" it.

The "white" is actually very pale pink. At least on my phone screen
- When I zoom in on my phone, it's absolutely white
  
  Must be hardware variant
- My phone makes it pink too. But you can still see some effective difference when zooming in/out.

Here is an 8 minute video that goes into more depth on how this works. https://www.youtube.com/watch?v=0FjjJha7HMI

This is one of those actually cool optical illusions

Weird but if I focus my mind so to say it appears white but then if I relax then again red

...I was gonna say it took until it was shrunk down to the thumbnail to see red, but nope, it actually has red in it in the thumbnail.

Guess this is specific to how often you see cans of coca-cola?
Here, I put the image through a ditherer (only available colours are black, cyan, white). I don't see any red at all now.
[edit}
Actually, that "red" is mostly just gray so I played myself here. Still, the luminosity must be closer to red before I detect it as red, white doesn't do it.

If you zoom in to see that it's black and white, and then zoom back out again, it stays black and white. But if you look away for a bit to forget, maybe change the angle you're looking at it, it turns red again.
- For me zooming out changes it back to red.
- I think it probably depends a bit on the color persistence effect. Like when you stare at something then look away, you see the opposite color. This effect probably requires the parts of your eyes that were looking at cyan to move over the white area and create red. So if you look at it without moving your eyes, it doesn’t work

Except that there is. Alright, maybe not exactly, but...
The whites that you see as white (in the other white parts which don't seem red), are shifted like #E0F9F8. Notice the reduced reds there.
The whites you see as red are shifted like #F9F9F7. This one, I'd probably call yellow, but you get the point, reduced blues. There's probably a better example pixel in there and I just haven't found it.
The red pixels in the thumbnail, well, maybe JPEG downscaling? I can't say, because I don't know what downscaling algorithm is being used.
So the parts you see as white, are actually bluish white in a sea of blue (Cyan is just mixtures of blue and green in case of RGB) and the part you see as red, are reddish white, in a sea or blue.
Also, for those who don't see red, don't look straight at the image. Look at something near it, with the image in your peripheral vision and you'll get what others are saying. But I guess that happened while you were reading the title.

Pretty sure this is stolen from a Facebook account I follow but I can't remember the name at the moment and will edit it in if I find it
Edit: the account name is Japanese
2nd edit: found it
https://www.facebook.com/share/6U4q8zuJr7usVgtk/?mibextid=qi2Omg

I only see the red when its small, in the thumbnail its red, but when I open the image its very black and white.
The white has more red in it than green and blue, so that's probably the cause of the illusion.

Here's another version
The poster in the image is the original source for the coke can op posted btw

I need to grab a color dropper but I am sensing a little warmth from the White even when I zoom in
- This is a screenshot of it zoomed in...
  You tell me if the white looks warm
  
  https://www.color-hex.com/color/fffcf9
  Looks warmer than #ffffffff that’s for sure
  There’s no disputing our minds are filling in red because we see a Coca-Cola can. But it does appear to me that there is a very very light thumb on the scale to make it easier
  
  I think what we actually need is someone to take a picture of their screen with a microscope while the image is zoomed out.
  Based on some comments I've seen, it seems likely this is just an artifact of how the red/green/blue pixel layouts work when drawing the edges of white things.
  Edit: I don't have something to check the actual display pixels, but I realized I could just rotate the image and see if the colors change, which they don't. So this definitely seems like more of a white balance effect, similar to that old Gold/Blue Dress meme.
  
  That doesn’t change anything but yes it does look a hair warm.
- Maybe you also try replacing cyan to magenta and see what happens. Imo the warmth of white does not do anything much
- FFFCFCF9
  
  I’m getting no hits for that do you mean fffcf9?

- Yeah. Shouldn't this work with e.g. a picture of a tree as well?
  
  indeed. I hate ads. Even more forced ads of liquid sugar. Would have loved to see that red tree if only to prove that its not about the familiarity to the item.

And what color does white have?

Great lectures on this kind of thing:
https://m.youtube.com/watch?v=af78RPi6ayE
https://m.youtube.com/watch?v=mf5otGNbkuc

Burn the witch!

Do I not see the color because I'm protan or what? Does that even make sense for optical illusions?

Is this because our brains have been programmed to see Coca Cola can as red? Or does it have something to do with the way the black and white boxes are organized? (I.e. if it were a sprite can, it would still be red)
- It's effectively your brain doing automatic white balance, it sees everything being tinted cyan so it just sorta subtracts cyan from the area, which results in white being reddish
  you can do this physically (by tiring out the colour-sensing cells in your eyes) if you stare at a colour for about 30 seconds then quickly look at a white surface, you should see the inverse of the first colour.
- Someone did a color swap and the can looks blue when the cyan pixels are instead yellow
  https://lemmy.world/comment/10968050
  
  How come this comment isn't clickable in the app, and you have to open a browser to see it?
- The cyan is the one playing the trick. I can see the black and white nature without zooming when focusing on the logo or something. Sometimes it randomly changes from b/w to red
- I think it's a bit of both. The light blue color used is so called "complement color", meaning it's exactly the opposite on the color wheel to the Coca Cola red. Black and white pattern suggests to our brain to play with contrast. And of course we all know Coca Cola from all the marketing.
  Btw, After staring at it for a while I can kinda switch between red and white at will. Anyone else?
  
  Interesting :) And yes, for me it also became easy to switch once I was aware of the truth of what I was looking at.
  If you look directly at the can you can see it as white, but if you look elsewhere and the can is only in your peripheral vision it seems to always be interpreted as red.
- I have myopia so if I place the phone far from my face I can't see that it is even a can... I still see a little bit of a red area there.

Hm.. when I glance at it, yeah I see the white is very very light pink. But once I focus on the details, I see no trace of red.
- I don't even see that. My brain must be broken.
  
  same... just white for me. maybe because I read the title first. idk