Are you confident that the sky is blue and grass is green? What about everything in between?
A viral test asking people to pin down the line where blue ends and green begins is showing that we could all see colours slightly – or significantly – differently.
The website and app ismy.blue shows users a series of colour blocks and asks them to click whether they are green and blue.
In this way, it determines where your personal boundary is on the colour gradient.
Interestingly, it then tells you where this falls compared to the average, with the results above received by a user more likely to see colours as blue.
It’s not a scientific test, as of course people will be viewing the test using different screens and in different lighting conditions, and may see things as differently as the did the famous dress in 2015.
The developers also found results differed by time, as in the evening users may have night mode switched on to reduce blue light and make the display more red.
But it’s a fascinating test nevertheless, and with over a million users since its launch in August, clearly lots of people agree.
Neuroscience and AI researcher Patrick Mineault, who created the site, said: ‘The validity of the inference is limited by the calibration of your monitor, ambient lighting, and filters such as night mode.
‘Despite these limitations, the results should have good test-retest reliability on the same device, in the same ambient light, which you can verify by taking the test multiple times.
‘If you want to compare your results with friends, use the same device in the same ambient light.
‘Getting outlier results doesn’t mean there’s anything wrong with your vision. It might mean you have an idiosyncratic way of naming colors, or that your monitor and lighting is unusual.’
If you’ve ever had a fraught debate about whether something is blue or green (just me? Apparently not) then this site is ideal, as now there is empirical data to work out who is correct.
And when it comes to the correct answer, Patrick said that in early experiments most people’s boundary clustered around the 175, ‘which coincidentally is the same as the named HTML color turquoise’.
He added: ‘This is interesting, because the nominal boundary between blue and green is at 180, the named HTML color cyan. That means most people’s boundaries are shifted toward saying that cyan is blue.’
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