Monday, May 18, 2015

Scientists publish study on TheDress that made us ColorBlind

Do you remember #TheDress ? If you don't, then good. Well, here it is again.


This may look like an innocent, but badly lit photo of a dress, but the fact is, this photo nearly broke the internet one day with the amount of netizens talking, tweeting, facebooking, pinteresting, and what not about it - all arguing about the color of TheDress.

Now, it is your turn.

Simple question :
What color is this dress ?
After you answer, ask a couple of your friends the same thing. No tricks - use the same mobile or laptop or tab or whatever, same lighting, same position, same everything  - different person.

Ask them, "What is the color of this dress ?"
There is a 50-50 chance that they answer the same as you. If they do, continue to the next person.
Soon, you will find a bunch of people who say it is "Blue and Black". And another bunch of people who say "White and Gold".

Some may say "Brown and White"

And some may change from one group to the other after a few hours,not believing that it is the same picture.

And, no, it is not because they are color blind.

And none of them refuse to believe what the other group says.

A perfect optical illusion.

Most optical color illusions work the same for everyone. But this was the first one(that I know of) that worked different for different people.


This above stripe, stripped of lighting cues and other distractors, still appears white and gold to me.

What does it look like for you ?




There have been multiple attempts at explaining the color of the dress.
Firstly, know that the actual dress is "Black and Blue". There are many better photographs of the dress which clearly show the dress to be "Black and Blue" for everybody.

But that is not the point. The point is that the photograph is a very unique Optical Color Illusion. Awesome !



Scientists have gone ahead and published 3 studies about the color of TheDress (paywalled)

Here is a summary from Cell.

There has been an intense discussion among the public about the colour of a dress, shown in a picture posted originally on Tumblr (http://swiked.tumblr.com/post/112073818575/guys-please-help-me-is-this-dress-white-and; accessed on 10:56 am GMT on Tue 24 Mar 2015). Some people argue that they see a white dress with golden lace, while others describe the dress as blue with black lace. Here we show that the question “what colour is the dress?” has more than two answers. In fact, there is a continuum of colour percepts across different observers. We measured colour matches on a calibrated screen for two groups of observers who had reported different percepts of the dress. Surprisingly, differences between the two groups arose mainly from differences in lightness, rather than chromaticity of the colours they adjusted to match the dress. We speculate that the ambiguity arises in the case of this particular image because the distribution of colours within the dress closely matches the distribution of natural daylights. This makes it more difficult to disambiguate illumination changes from those in reflectance.


Another one published on 14 May, 2015

‘The dress’ is a peculiar photograph: by themselves the dress’ pixels are brown and blue, colors associated with natural illuminants , but popular accounts (#TheDress) suggest the dress appears either white/gold or blue/black . Could the purported categorical perception arise because the original social-media question was an alternative-forced-choice? In a free-response survey (N = 1401), we found that most people, including those naïve to the image, reported white/gold or blue/black, but some said blue/brown. Reports of white/gold over blue/black were higher among older people and women. On re-test, some subjects reported a switch in perception, showing the image can be multistable. In a language-independent measure of perception, we asked subjects to identify the dress’ colors from a complete color gamut. The results showed three peaks corresponding to the main descriptive categories, providing additional evidence that the brain resolves the image into one of three stable percepts. We hypothesize that these reflect different internal priors: some people favor a cool illuminant (blue sky), discount shorter wavelengths, and perceive white/gold; others favor a warm illuminant (incandescent light), discount longer wavelengths, and see blue/black. The remaining subjects may assume a neutral illuminant, and see blue/brown. We show that by introducing overt cues to the illumination, we can flip the dress color. 


Whatever the explanation, it was a really cool color illusion 

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