White and gold dress: Here's the science behind why some people see blue

White and gold dress: Here’s the science behind why some people see blue

10:22, 27 February 2015 By Olivia Solon

What colour is #thedress? The whole internet is confused – but science has an explanation

The entire internet is confused about this dress. Do you see it as white and gold or black and blue? Some even see it as blue and gold.

We know that the actual dress – from British retailer Roman Originals – is royal blue and black. But the it’s the low quality photo – taken by this Tumblr blogger – of the dress that has flummoxed us all, and triggered a flurry of hilarious memes.

So why is that we all see it differently?
The original dress is definitely blue, but the photo of it is very confusing to human brainsThe original dress is definitely blue, but the photo of it is very confusing to human brains.

It comes down that the way that human eyes have evolved to view colour in a world where the main source of light is sunlight.

We see the objects around us because light bounces off them and back onto our retinas. The brain has learnt to register what colour the actual light source is and then subtract that colour from the actual colour of the object.

So imagine a yellow-y light on a white object – the brain understands that the yellow light is influencing the colour of the surface it’s landing on and will try and ignore it.

Does this photo look blue or gold to you?

Human eyes evolved to understand the difference between the colour of the light source and the colour of the object
Humans have evolved to deal with a range of coloured light, since we’re used to the sun shifting through a range of colours from sunrise to sunset, with more yellowy and red colours at either and of the day and more bluish white colours in the middle of the day.

“Our visual system is supposed to throw away information about the illuminant and extract information about the actual reflectance,” neuroscientist Jay Neitz, from the University of Washington, told Wired.com.

Some of our brains cut out blueish tones while others cut out yellowish tones

Some brains are subtracting blue “light” while others are subtracting yellowy gold tones

In the case of the blue dress, the brain is trying to subtract the colour bias caused by the light source. But some people’s brains are trying to get rid of the blueish tones – so they will see white and gold – and some are trying to get rid of the yellowy gold tones, which means they’ll see blue and black.

“But I saw it as one colour and now the other”
Even weirder is that some people will initially see it as white and gold, but then look at an enhanced version of the picture and then see the different version.

It does to show the importance of context in how our brains process images. There are lots of other mind-boggling optical illusions that demonstrate this.

For what it’s worth Neitz sees white and gold and says: “I’ve studied individual differences in colour vision for 30 years and this is one of the biggest individual differences I’ve seen.”

What colour is #TheDress?