36

By now pretty sure the entire world is familiar with the "dress" optical illusion as it will one day be known. My question is how can this illusion be reproduced on other images?

For those living in the social media dark ages, here is the image:

white and gold or black and blue

In general terms, some people have to refocus in order to see the correct colors of Black and Blue. It is possible to re-"tune" your eyes and see the Gold and White but very difficult. For the most part once you see it Black and Blue you can't go the other way.

Again though - the question is how can this illusion be reproduced in order to use it in various designs?

1

10 Answers 10

34

Edward H Adelson created a Checker shadow illusion in 1995.

enter image description here

From wikipedia:

The checker shadow illusion is an optical illusion published by Edward H. Adelson, Professor of Vision Science at MIT in 1995.1 The image depicts a checkerboard with light and dark squares. The optical illusion is that the area of the image labeled A appears to be a darker color than the area of the image labeled B on the 2D plane of the rendered 3D projection. However, they are actually exactly the same color on the 2D plane of the image file (but not necessarily in the 3D projection) which becomes especially obvious if the projected 3D scenery is rendered partially or entirely defective.

That the two squares are of the same color on the 2D plane can be proven using the following methods:

  • Opening the illusion in an image editing program and using the eyedropper tool to verify that the colors are the same.
  • Cut out a cardboard mask. By viewing patches of the squares without the surrounding context, you can remove the effect of the illusion. A piece of cardboard with two circles removed will work as a mask for a computer screen or for a printed piece of paper.
  • Connecting the squares with a rectangle of the same color, as seen below in the middle figure.
  • Using a photometer.
  • Print the image and cut out the squares. Cut out each square along the edges. Remove them. Hold them side by side.
  • Isolating the squares. Without the surrounding context, the effect of the illusion is dispelled. This can be done by using the eyedropper tool in image editing programs, such as Gimp to sample the values of A & B, and to color in the newly adjacent rectangles using the paint bucket tool.

Spoiler image -- mouseover to see:

image with 'difference' edited in

This is really just a different take on the same illusion. The surrounding areas of color alter the human perception of the internal items.

It is the drastically poor photography, and the subsequent blow outs in the background, which can alter the perception of the dress. If the photography weren't as horrible as it is, there would be no "illusion".

To be fair, I've never attempted this same illusion on an image myself. But it seems to me in order to recreate the same type of illusion one must surround the image with colors and values closely related to the existing colors/values of the image. Basically the background needs to have the opposite value/color of the internal item. Patterns within the image become almost mandatory so that the eye breaks up any solid color/value field. The illusion won't occur with solid colored objects. The combination of an internal pattern which fluctuates between the the background value and the image value creates a discourse in the eye allowing the viewer to see either A or B.

I think the trick to the dress is that in an RGB display the B values between the dress and the background are opposing. The background is strongly yellow... the opposite of blue in RGB.

And full disclosure... I don't see how anyone could see that dress and anything other than blue and black (or rather a blown out black so ... muddy brown). Even looking at @Vincent's answer.. the dresses are blue here. Perhaps this particular image relies on poorly calibrated displays and one's own interpretation of what "white/gold? may be? All I see is a blue or a lighter blue.. never what I would refer to as "white".

10
  • I've seen the same thing but with a Rubik's cube, and the alternating color was brown vs. orange. But ... "A appears to be a darker color than [..] B": you know I'm going to measure that, right? Coz obviously it is!
    – Jongware
    Feb 27, 2015 at 17:48
  • @Scott I saw it as Gold and White originally. I think its because I was reading a book before looking at it so my eyes were calibrated for that task. I know that's how I was able to get a friend of mine to see white and gold as well.
    – Ryan
    Feb 27, 2015 at 17:50
  • 2
    Measure away... I know I had to when I first saw it :)
    – Scott
    Feb 27, 2015 at 17:51
  • Oh what confidence. I'm mentally preparing to eat my words 😄 (Hey look, they both are shown here: serendip.brynmawr.edu/bb/contrastcolor)
    – Jongware
    Feb 27, 2015 at 17:52
  • 2
    This is absolutely not the same effect. As far as I know, everyone sees this in the same way and is amazed by it. On the other hand, the perception of the dress is very divisive, and unlike most optical illusions, very stable.
    – mattdm
    Mar 2, 2015 at 14:36
32

It's a rather simple optical illusion, really--the colours of the environment influence how you see the dress's colours. I could elaborate, but xkcd's Randall Munroe has explained it with just a single picture:

xkcd's explanation for TheDress. Source: xkcd.com

The two dresses in this illustration have the exact same colours: #879abd for the blue and #715e3a for the gold.

edit: To actually answer Ryan's question a bit more: I think the confusion comes from the fact that lots of people don't see the complete image when they first come across it. Because the surroundings are unclear, we subconsciously try to add in what those are. If we add in an environtment with a bright light, we see a black and blue dress. If we guesstimate that the surroundings are dark, we see a gold and white one.

To actually reproduce this effect would require everything but the colour-ambiguous area to be unfocused or made unclear in another way. Causing the picture to initially be seen partially, or at a smaller size (obscuring things even more), would help the ambiguity and thus the illusion.

11
  • 9
    Bother dresses still look blue to me.. just one appears to be a lighter blue than the other (thus the illusion). Still no idea how anyone could call that "white".
    – Scott
    Feb 27, 2015 at 18:04
  • 3
    @Scott Because white objects appear blue when lit by daylight in shadow (shadow = no direct sunlight, but plenty of sky light).
    – Random832
    Feb 27, 2015 at 18:34
  • 11
    I still don't see any "black". I see a light-blue-with-gold dress on the left, with a slightly-darker-blue-and-slightly-darker-gold (perhaps "brown") dress on the right. Feb 27, 2015 at 21:38
  • 4
    This can't possibly be the correct explanation. People who see the dress as white are seeing it against precisely the same background as people who see the dress as blue.
    – Jack M
    Feb 28, 2015 at 15:34
  • 3
    @JackM some cognitive psychologist just said its because you get so little background info that's the brain guesses. Thus you can see both depends wildly on what you look ad at first.
    – joojaa
    Mar 1, 2015 at 12:52
22

It's a matter of whether your brain thinks it's a dark dress under warm (yellow) lighting, or a light dress in a shadow.

dress in different lighting

(I take no credit for the above image)

For the record, here is the actual dress. The black shows up as gold-tinted in the picture because of the massive over-exposure under a warm (yellow) light.

6
  • 2
    The question is how to create the effect on other images. Not seeing how this answers that.
    – Ryan
    Feb 27, 2015 at 22:13
  • 1
    @Ryan the point is you need make a situation that could plausibly be either. For example, the presence of a bright light in the background, from which a shadow could have been cast.
    – Random832
    Feb 27, 2015 at 22:39
  • 1
    @Ryan The only way to recreate the optical illusion is to understand it. I don't see how this doesn't answer the question, anymore than the top-answer anyways... Feb 27, 2015 at 23:16
  • 1
    @BlueRaja-DannyPflughoeft The original illusion was a single image which is interpreted differently by different people. This is two images which are interpreted the same way by everyone - everybody perceives the left dress as blue and the right dress as white.
    – Jack M
    Feb 28, 2015 at 16:00
  • That image allowed me to see how my eyes could retune if I focused quite a bit. Couldn't see the black/blue before then. No more fighting! :-)
    – curious
    Mar 2, 2015 at 0:40
10

Beau Lotto's Ted Talk on this subject is an absolute must watch if you are curious about the dress optical illusion.

http://www.ted.com/talks/beau_lotto_optical_illusions_show_how_we_see

I could not possibly say it better than he does, so I am going to quote some of the relevant transcript. As he is a predominant expert in the field, please consider his opinion to be reinforced by fact.

Why is this illusion happening?

The light that falls onto our eyes is determined by multiple things in the world -- not only the color of objects, but also the color of their illumination, and the color of the space between us and those objects. You vary any one of those parameters, and you'll change the color of the light that falls onto your eye.

This is a huge problem because it means that the same image could have an infinite number of possible real-world sources. Completely different meanings, giving rise to the exact same retinal information. And yet it's only the retinal information that we get. The light that falls on to your eye, sensory information, is meaningless, because it could mean literally anything.

So, how do we see? Well, we see by learning to see. So, the brain evolved the mechanisms for finding patterns, finding relationships in information and associating those relationships with a behavioral meaning, a significance, by interacting with the world.

Our brains can redefine normality, even at the simplest thing the brain does, which is color. Take two identical squares, and put them in light and dark surrounds. And now the one on the dark surround looks lighter than the one on the light surround. What's significant is not simply the light and dark surrounds that matter. It's what those light and dark surrounds meant for your behavior in the past.

Notice that on the left the two tiles look nearly completely opposite: one very white and one very dark. Notice that on the left the two tiles look nearly completely opposite: one very white and one very dark. All right? Whereas on the right, the two tiles look nearly the same. And yet there is still one on a dark surround and one on a light surround. Why? Because if the tile in that shadow were in fact in shadow, and reflecting the same amount of light to your eye as the one outside the shadow, it would have to be more reflective -- just the laws of physics. So you see it that way.

So this is slightly cut up from the video, and it is basically him describing how our brains will learn, by defining normality, how to see. And as a result, that definition can affect how we interpret the visual information we are receiving.

Please watch the video for more context, he has visual aids that I did not feel copying here as it seemed slightly plagiaristic.

How can it be reproduced?

This can be visually reproduced by "teaching" the user's sight to learn to look for certain colors or shades and then showing them something which would look differently if seen in a different shade.

Essentially this is all done with color and intensity contrasts. For example, a light grey on a dark background will look darker than a light grey on a light background.

A very simple exercise with the exact image in this post would be to close your eyes for 30 seconds, and look at the white portion of the dress as you open them. It will look tinted, and the colored portion will look darker. This will illicit the blue and black response. Next, let your eyes adjust to ambient room light, then look at a light bulb for 3 seconds and then look at the dress again. The lighter colors will show through, and the white look like brighter, and the orange will look colorful.

0
9
+250

Since you asked about color theory, I assume you are already aware of color theory and know a little of how it relates to shadows and highlights. If not, take a look at this article which does an excellent job of explaining how to create objects with shadows when painting.

We can use this information as a tool for creating similar images as this dress. However, it is worth pointing out that the reason why it is so easy for our minds to misperceive this image is because this is a grainy, poor quality jpeg and the lighting is considerably complex.

In fact, part of the reason why this effect is occurring is because this image was taken on a mediocre camera (almost certainly on a cell phone), snapped quickly (causing a bit of blur), and likely scaled-down in quality so that it would be easy to upload to a social media site.

The bottom-line is that for the ocular portion of the nervous system to make a good judgement of a scene, it needs quality "data" coming in. If our brains receive poor data, then it can easily make poor perceptual judgements.

Regarding this image, the lighting is as such that many tend to first notice the really BRIGHT source of light, coming from the window. In our minds, we then assume "Ok, bright light outside, ergo... I must be looking at the shadow-side of this dress."

Being armed with our knowledge of blue-toned shadows and using complementary colors for shadowing, we can now understand why we may perceive that this is a white dress (that is being toned down to a bluish tone for shadowing) and that the gold lace is also being cast in a bluish tone because it is also in a shadow.

For those of us who misinterpreted this scene, we may have to stare at this image for a minute for our minds catch that there is a lot of light-bleeding from light glaring on the lens of the camera.

This means that instead of seeing a dress in a shadow, we are actually seeing it in a room that also has a very-bright light shining on the dress. Our minds then go:

"Oh! This isn't a dimly lit, white/gold dress, it's a well lit black/blue dress! Let me slooooooowly re-adjust our perception so that MAYBE we won't think we're complete idiots..."

We are fooled because both the Black/Gold and White/Blue color-pairs in this image are both close to the center of the complementary color gradients for each color. Since we are close to that center-point of the complementary color scale, and the image quality sucks, our minds simply don't know how to correctly process this image.

How do we use this to our advantage?

I can't give a straight-forward answer because using this information effectively requires a considerable amount of artistic capability in setting up a scene. Though I'm no artist, I can offer some tips.

First, I'd setup a scene with an immediate focal point that isn't the object that you want to use as your "confused" focal point. In the case of our image, this is the very-bright light coming from the window. Make this the first perceived focal point by your viewer and make it, dare I say it, rather garish.

Next, device a scene where an object rests in a place that one would assume is a shadow. As I mentioned, our minds tend to think this dress is in a dark room. If the room is dark, we are seeing shadowed-tones. Create this same effect by using complementary, shadowy colors, but be sure to use colors that are all very close to that grayish-blue tone that is somewhere in the middle of all high-to-low light complementary color scales.

Next, recreate a "light bleeding" effect like the one we see on this image from the light that was shining on the lens of the camera. In fact, this bleeding effect is almost certainly necessary. I can't see how else one could fool the mind without it. It is this light-bleed that makes our minds miss that the object-of-focus is actually well lit, rather than poorly lit. This is a necessary mechanism if we want to fool the mind, and have your viewers question what they are perceiving.

If you can follow these rules, and with a bit of practice, I think you could recreate a similar effect within a digital image, or possibly even a painting. I would mock-up an example of this type of image but this is extremely difficult to replicate. As Scott posted above, the cylinder with the shadows on the checkerboard show a good example of how our minds alter real color, so that we can get a better understanding of what an object really looks like, regardless of lighting, in a three-dimensional world.

However, your end-goal is to create a scene that the eye can't easily correct and, in fact, will misperceive! This will require a certain level of artistic creativity and a lot of experimentation.

Anyway, if you are an artist and hope to recreate this type of illusion in your work, then good luck! I'd love to see someone play off of this psychological effect in art. It's fun to observe and, for a second, makes most of us question our sanity when we are strikingly made aware that the world is often not as we immediately perceive.

2
  • I think this is the closest answer so far and as I was going to make my own answer wanted to instead ask if you mind me making some edits to yours? Everything you put is correct but my research turned up some additional information that could also help someone potentially recreate it. You mind me making edits? If so I'll make a separate answer instead.
    – Ryan
    Mar 3, 2015 at 19:08
  • @Ryan, feel free to edit this as you suppose. Thanks for asking.
    – RLH
    Mar 3, 2015 at 19:34
8

This is sort of a sideways answer at the question. I’m challenging the idea that this is an optical illusion and have a different theory. Maybe this instead is a case of widespread, partial color-blindness. My friend and I both see blue and black (dark brown?) and have not been able to “re-focus” to see any other colors. Likewise, our wives see white and gold and cannot alter their perception; maybe just from pride :). Our idea was that perhaps they simply aren’t able to see a shade of blue prevalent in the image.

So, to demonstrate the point we opened the original poster’s image in Photoshop, used a color dropper to ensure that it was indeed blue in the source and then removed that color from the color channels. Viola, now we all agree that the dress is white and goldBlueBlackDressIsNowWhiteAndGold

Here is the blue we sampled from the image and then removed from the original: enter image description here

7
  • 2
    I saw the blue/black from the very first moment, and a bit earlier was able to see the white/gold for the very first time (on the original unmodified image). So unless this “widespread, partial color-blindness” turns itself on and off randomly, I’d say this is something else instead ;)
    – poke
    Feb 27, 2015 at 20:24
  • Question is how to recreate the effect - not seeing how this answers that.
    – Ryan
    Feb 27, 2015 at 22:14
  • 1
    Still looks like a blue dress to me. I think the internet has gone crazy and the fact that this has gained so much steam is a sad commentary on the world and what people find important in it. :)
    – Scott
    Feb 27, 2015 at 23:34
  • 5
    So, if you remove the blue, it no longer looks blue. Who would have thought it?
    – Doorknob
    Feb 28, 2015 at 3:00
  • 1
    This is a viola, you're looking for voilà.
    – Etheryte
    Mar 2, 2015 at 11:44
6

I don't know the real answer. In fact, I can't really get this illusion to work for me. To me, it looks like a really crappy color corrected (or purposefully manipulated) bad photo.

But, I have two theories...

The first is the above mentioned fact. This photo's exposure is blown out and heavily artifacted. If you look at the image from the top down, you do notice that the 'true' colors in the image d0 lean towards gold and a very cool off-white in terms of the actual pixel values:

enter image description here

Without taking the rest of the photo into consideration, one could easily 'color adjust' that photo in their brain either way...towards gold or towards black. It's such a badly lit and exposed photo, that the amount of mental color correcting people have to do is adding variability to the results.

There is a strong correlation to art, here, in that photographing or painting real objects, one should never use true black and true white, as they are actually quite un-natural in the real world. If you look around the world you are in at anything white or black, you will notice that they never are 100% white or 100% black. They reflect other colors, lighting dilutes the color, etc. It's only in context of colors surrounding them does your brain then make the calculation that something is actually black or white.

However, in the context of the full photo, I have a hunch most people properly 'color correct' it in their heads to the proper blue/black. Those that don't initially do that perhaps have an overly-narrow focus (possibly due to them looking at this photo in the context of a 'focus on the effect') or...my second theory...they're color-correcting it to gold and white because that's the very title of the effect. The effect is implanted on your brain before even seeing the photo.

5
  • You might actually be on to something. The first time I saw it I was scrolling slowly down facebook reading things and it appeared Gold and White. Perhaps if you see it that way first instead of as one whole image it facilitates the illusion
    – Ryan
    Feb 27, 2015 at 18:34
  • 1
    @Ryan another complication with this 'effect' is that it's entirely on-screen. I wonder if there's a strong correlation to the color's people are seeing and the quality of their screen.
    – DA01
    Feb 27, 2015 at 18:36
  • I wonder how many people who say "white" really mean light blue?
    – user28415
    Mar 2, 2015 at 7:02
  • It's really interesting to me that people describe isolated color of the dress as "a really cool off white". I suspect this is an artifact of identifying the dress as white initially and still having that strong in your subconscious. I would be really shocked if people not part of this dress discussion saw RGB #a3b7e9 and identified it as anything other than light blue — and that's the lightest blue patch (that isn't blown out) in your sample above. The main middle part of the dress averages to #7583b1 (taken from the average of a stripe without the ridge shadow).
    – mattdm
    Mar 2, 2015 at 15:29
  • FWIW, color-blindness.com/color-name-hue names the first of those "Perano (hue: Blue)" and the second as "Wild Blue Yonder". Not that that's authoritative. And I'm not arguing with your perception of the image; I just find this difference in perception incredibly fascinating.
    – mattdm
    Mar 2, 2015 at 15:32
5

The only illusion here is the leading question suggesting the light areas are white, along with the binary choice. This is a visual hybrid of the forced card trick and a "false choice."

In fact there is measurably no black in the image at all, so neither choice is accurate.

I think Random832 has a point though: we all accept that whites gain a color cast in different conditions, especially at times when there is low light.

Whatever color the real dress is is a red herring and has no bearing on our evaluation of the blown out photo.

enter image description here

4

I don't think this would work with any color other than blue, because it's an ingrained assumption that white objects in shadow appear blue (because the sky is blue, and something outdoors in shadow is generally still being lit from all around by the sky).

As for how to reproduce it, I think the very bright light coming from behind it (that obviously is a light, rather than e.g. a plain white background) is a key factor - that's what makes people think that the dress is in shadow, and thus see it as "colors that would look like this in shadow".

6
  • Natural light is only ever-so-slightly considered 'cool'. It's typically considered the 'neutral' for most people between cool (blues) and warm (yellows) light...and early morning/early evening things shift towards the warmer side.
    – DA01
    Feb 27, 2015 at 18:42
  • 1
    "Natural light" includes direct sunlight as the dominant source of light. I'm talking about objects in shadow where the only light source hitting them is the sky, not the sun. A clear sky is not merely cool but is in fact bright blue. And a white object outdoors in shadow will be the same color as the sky, because white objects are the same color as whatever light is hitting them.
    – Random832
    Feb 27, 2015 at 18:44
  • We may be on the same page here just interpreting things a little differently. The sky is blue, but doesn't 'project' blue light. The reason the shadows (and the sky) both appear blue is due to light scattering: en.wikipedia.org/wiki/Shadow#Color_of_shadow_on_Earth So, shadows are blue like the sky, not because the sky is blue.
    – DA01
    Feb 27, 2015 at 18:59
  • It's a blue light source for the purpose of lighting a scene, though. The light that arrives in a shadow does so because it came (most recently, after being scattered) from a direction other than that of the sun (which is blocked by the object casting a shadow).
    – Random832
    Feb 27, 2015 at 19:24
  • Yes, we're in agreement...just quibbling over wording.
    – DA01
    Feb 27, 2015 at 20:05
3

The thing with colour is that our brain calculates colour and it can get this wrong at times or autocorrect it depending on the light around.

On cameras you will normally find a setting called White Balance and using this you can see exactly how our brain auto-corrects colours.

On the white balance mode try setting it to something other than Auto White Balance (AWB) like for example Daylight mode or even better manual and point the camera at something white outside in the sun and get it to manual set the balance from that - some cameras like most of the Canon range have a manual white balance option - for the Canon's you have to set it to manual mode, point at something white and the press DISP button normally to set the balance), take a picture outside in daylight, then take a picture inside under a normal light bulb, and then take a picture under an energy saver/fluorescent bulb - preferably in each case have something that appears to be pure white in each one - maybe take a picture of a white sheet.

Now look at all three pictures and what do you see - it's weird isn't it - when you were in the daylight the colours in the picture look normal, but the pictures that were taken under the two different light bulbs both have like a different colour haze over them (if I remember correctly the ones under the normal light bulb should have a yellowish haze over them and the ones under the energy saver bulb/fluorescent should have a blue haze over them - you'll see it more if you look at the white item you took).

So why on earth did this happen (and no it's not because you didn't use Daz washing powder on the white sheet - although washing powder does use a similar trick - in case you haven't watched Theory of Everything yet in the beginning Steven Hawking's explains that one!)

The reason is because light that we see is not always 100% white. Fluorescent bulbs actually produce a bluish light, and tungsten bulbs produce a yellowish light, but your brain realises that the light source is affecting the colour in the room and so it tries to automatically compensate for that and uses other things to figure out the true colours - same way a camera figures it out using auto white balance. But in some cases it gets really confused and what you see is totally the wrong colour.

In addition to this the brain also uses shadows to figure out what the colour of something is, but sometimes shadows can be wrong too and that can cause major problems for our brain to figure out the true colour of something.

To recreate this dress optical illusion you would need to find some kind of material that could in places give the impression that a shadow is being cast in certain areas and not in others to fool the brain into thinking there is shadow there and the colours are different when in fact they're not.

There is an image here of a rubiks cube that does a similar trick, the colour on the top square is the same colour as the square on the side but they appear totally different - I've drawn a line in the same colour connecting one to the other and if you look at the line it appears to have a gradient as it goes over the side of the cube, but in actual fact it's all the same colour.

rubiks cube optical illusion

And one final thing if you want to see what white balance can do - take a look at my Youtube video that I did last year at Wakestock - https://www.youtube.com/watch?v=PkoEqr8Cz7I - the colour is very far out on a number of shots 'cos I'd left the white balance by accident set wrongly during the filming. I did try and correct it a bit but you can still see the very wrong colours all over the place.

3
  • I don't buy the "your brain does the white-balancing" explanation. If this were correct, we wouldn't need to white balance photos in the first place, because people's vision system would do it when they see the photo. But that doesn't happen. Typically, if someone sees a photo of a white dress taken outdoors but white-balanced for indoor tungsten, that person says "why is there a weird blue across this whole photo?" or "what instagram filter did you use?" — not "oh, that's a white dress, and I don't even know what you're talking about when you say blue", which is what's happening here.
    – mattdm
    Mar 2, 2015 at 14:44
  • @mattdm Our brains do white balance the photos we look at, according a complex combination of the colors in the photo and the environment around the photo. That is how your brain can tell that an incorrectly balanced photo is overly blue or yellow and not balanced. Try looking at such a photo on a screen in a dark room. Mar 4, 2015 at 8:48
  • Or to put it another way, the reason we need to white-balance photos so they are more “neutral” is precisely so that we don’t confuse the eye with conflicts between the light sources inside and outside the image. That confuses the eye as to what the “true” colors are, just like the dress image does. For another good example, look at images with a mixture of strong indoor and outdoor lighting, or strong indoor lighting and flash. Your eye will properly correct some of the image, but other parts will end up looking unnaturally blue, yellow, purple, green, orange – much like the dress photo. Mar 4, 2015 at 22:06

Not the answer you're looking for? Browse other questions tagged or ask your own question.