Science and Technology news - Science Can Tell You the Color of the Dress

Science explains how people can look at an identical object and see it differently

A raging debate has divided families, friends and work colleagues: What is the color of this dress?
A photograph of the two-tone outfit, made by British retailer Roman Originals, was initially posted on Tumblr on Wednesday by a user with the name “swiked,” who said that her friends couldn’t agree on its colors. Some said that it was gold and white. Others insisted that it was black and blue. Since then, the debate—and disagreement—has gone global.
Taylor Swift, Kim Kardashian and Justin Bieber have all tweeted their views. Millions of others have waded in via Twitter , Facebook and other forms of social media.

So what is going on? How can two people look at a photograph of the same object and see different colors?
Science has an explanation.

ENLARGEA photo of the dress posted on Tumblr on Wednesday, pictured, sparked the debate over its apparent color. Photo: http://swiked.tumblr.com/

Almost half of the human brain is devoted to processing visual information. What we perceive as color is the result of five factors that are compounded together. In the case of the dress, the first is the dress’s material, including the pigments it contains and how much light it reflects.
The second factor is the nature of light in which the object is viewed. An object will appear to be red whether it is in direct light, phosphorescent light or even fading twilight. Indeed, our brain does a lot of work to make sure we still see it as red, no matter what the illumination.
Scientists call this trait color constancy. It has helped our species to evolve. “You need to decide whether an apple is ripe to eat, whether it’s sunny or gray,” said Stefano Soatto, a professor of computer science who specializes in the science of vision at the University of California, Los Angeles.

‘There is no clear-cut or ‘dominant’ response from the red, green, blue receptors in the retina. What happens instead is a complex combination of responses, which is interpreted differently by different individuals.’

Another factor affecting color perception is the sensor involved—in this case, the sensor in the camera that took the picture. The display (your computer or gadget screen) also has an effect. And finally, the retinal sensors and visual machinery of the brain also play a role in color perception.
In the case of the mystery dress, the first four factors are exactly the same for two individuals looking at the photograph of the outfit. But it is a variation in the fifth factor that accounts for why two people perceive its color differently.

If we want to identify a point in three-dimensional space, we need three values: X, Y and Z, representing the coordinates in space. Similarly, in identifying a color, our brain uses the three coordinates of R, G and B (the primary colors red, green and blue).

But because our retinal sensors and brains are slightly different, our perception of color can vary. The dress is a particularly striking example of the phenomenon because its colors aren’t close to pure red, pure green or pure blue but instead are a complex mixture of those colors.
For this reason, there is no clear-cut or “dominant” response from the red, green and blue receptors in the retina. What happens instead is a complex combination of responses, which is interpreted differently by different individuals.

“What color is this dress?” sparks fierce debate on Twitter and in offices. Columbia University's Dr. Kenneth Miller explains why we see different colors. Photo: Facebook/Caitlin Jae

Prof. Soatto notes that despite the social-media ferment, the phenomenon isn’t that rare at all.
Some time ago, Prof. Soatto’s wife bought him a Burberry trench coat. The professor says it is yellow. His wife is convinced it is green. A friend maintains that it is gold. “We still haven’t settled the matter,” said Prof. Soatto.
So what color is the Roman Originals dress? If you can trust your eyes, the picture on the retailer’s website makes the answer clear: The dress is blue and black.
Write to Gautam Naik at gautam.naik@wsj.com






 

The first article I read about the dress did not give the majority view of the color until the end. I assumed most people would see a white and gold dress because I  did.  
 I still wonder if eye health matters.   I have several vision deficiencies.   For example is my lack of blue cones related to keratoconus?   Do people with perfect acuity also have better color vision or are the traits independent?   Is there a  gender difference in color vision?