It’s merely a blurry photo of a dress, taken on a mobile phone in poor lighting, and yet on Friday it transfixed the world.
This little white – or blue – dress has become an internet sensation, with everyone from scientists to celebrities weighing in.
Some respondents claim they see a blue and black dress, while others claim to see a gold and white dress.
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Others even report perceiving an olive green colour, a lilac or a dark brown.
Even Photoshop’s trusty colour detection tool can’t provide a clear answer as to what’s in the photo.
You can track the evolution of the debate – and which side is winning – on Twitter, where the subject generated millions of tweets in a matter of hours.
Why is this photo so confusing?
According to Dr Simon Cropper, senior lecturer at the University of Melbourne, the photo itself isn’t doing anyone any favours.
“If you saw the dress in real life there’d be no question,” says the vision and perception expert, who is in the gold and white camp.
“One thing I’ve noticed is that it’s a colour context effect – the surroundings and lighting presented with it will drastically change how it appears.”
Neuroscientist Jay Neitz, from the University of Washington, concurs that the photo is unique in its ability to confuse the visual system.
“I’ve studied individual differences in colour vision for 30 years,” he told Wired.com.
“This is one of the biggest individual differences I’ve ever seen.”
According to Dr Cropper, “the size, resolution and brightness of the screen you’re using will drastically change your perception of the dress”.
Indeed, this Vine video of the dress changing colour along with the screen brightness seems to suggest as much:
Why am I seeing what I’m seeing?
According to Mr Cropper, those who are seeing darker, blue-hued colours are taking a surface reading of the image, without taking into account contextual factors like the backlighting and shadow.
People seeing gold and white are processing the dress in relation to its surroundings.
It could also be a biological thing.
“Difference in perception tends to occur on the blue spectrum because some people have more blue cones in their retinas than others,” Dr Cropper says.
So, if you’re seeing blue and black your eyes are likely more sensitive to blue tones than others.
What colour is the dress, really?
According to the woman who originally posted the image, in the flesh the dress appears to be black and blue.
Scottish musician Caitlin McNeill first saw the dress when the mother of the bride at a wedding she attended sent the photo to her daughter to get another opinion.
“We all went crazy trying to figure out why some people were seeing white and gold, and others saw blue and black,” McNeill told Buzzfeed.
According to Ms McNeill, who saw the dress in person, it is clearly blue and black in the flesh.
A photo of the dress taken from the official site of its brand, Roman Originals, supports her point:
In a nutshell…
The dress is blue and black.
However, in regards to the photo there really is no wrong or right answer.
As a result of unique lighting and poor photo quality, a black and blue dress is appearing as gold and white to many due to contextual elements within the photo and biological factors specific to the individual.
Have your say
NB: The New Daily has not digitally altered this image.