function generateColors(difficulty, blacklist) {
        ...
        let sample = Math.floor(Math.min(Math.max(0, 1-Math.pow(1-difficulty, 1.5)), .99)*5);
        let distance = (5 - sample)/5;
        ...
    }
    function setupRound(blacklist) {
        ...
        const data = generateColors(currentRound/totalRounds, blacklist);
        ...
    }

    round#  difference
     0-- 2  5
     3-- 5  4
     6-- 9  3
    10--13  2
    14--20  1

Marginally related. I paint oils as a hobby, and my studio gets northern light, usually overcast and cloudy, during the day. Differentiating tiny color variations under those conditions is very easy, and in general your objective "pitch perfect" impression of color is also pretty accurate. However, I've painted in the same room at night under a "warm" LED bulb, and been absolutely shocked at how wrong and blue everything turned out when seen in the light of day. Not just that, but the hues I intended to be close to one another are much farther apart than they appeared under LED lighting.

So if lighting conditions can shift not just your perception of a color, but also its relationship to the ones around it, then I think how much more does your screen gamma and range alter that? A fair test would be printed on the exact same Heidelberg in 4 colors.

“As part of the next video, which will be out in a few weeks, l'd like to invite you to take part in an experiment about color perception. If you don't experience color blindness, l'd greatly appreciate it if you could take this test. Feel free to try it as many times as you like, think about it as a game!”

[0] https://youtube.com/@scienceclicen

I wonder how much of this would come down to screen calibration / color accuracy? If everything's consistently off in 1 direction I guess not much, but I would imagine certain shades might appear effectively the same on some cheaper screens?

And related, I once had an 'eye migrane'. During that half an hour, the figures of a clock disappeared the moment i looked at them.

Are you among the 1 in 255 women and 1 in 12 men who have some form of color vision deficiency? If you work in a field where color is important, or you’re just curious about your color IQ, take our online challenge to find out. Based on the Farnsworth Munsell 100 Hue Test, this online challenge is a fun, quick way to better understand your color vision acuity.

https://www.xrite.com/hue-test

(My memory is that the full test used to be online.)

By the way, I keep Night Shift enabled all the time: <https://i.imgur.com/LGkSlJZ.png>. I don't know how much it matters in a game like this.

See also <https://susam.net/myrgb.html> for a colour guessing game I wrote last year.

Interesting idea though. I wonder what the distribution looks like?

As others have said, a lot of this also comes down to what monitor and OS you're using, glossy/matte screen type, interior lighting and how everything is configured. This will be a lot easier with an OLED and all but impossible with an old TN panel. And whether HDR is enabled or sRGB mode, etc.

I have two monitors stacked vertically and this loaded on the top one and I'm fairly sure the latter was as big a factor as actual difference for the least-varying challenges.

I’m not in any way involved with art or graphic design or have any experience working with anything to do with colours so I can’t chalk it up to experience.

At about 13/20 they all started to look the same. I even turned off truetone at like 16.

I ended up scoring 15/20, but it's more like 12/20 and 3 lucky guesses.

But then I'm well known to not know or care about subtle colour differences.

Wonder how big an influence the type and quality of screen has. Do OLEDS give an advantage for instance?

At the end it says I can play again, because it'll generate more data. But for what?

It'd be cool to see some stats, or learn a bit more about what I just did...

I'd be curious to see some sort of score for each in terms of similarity in terms of human perception, just to get a scale of difficulty.

I think this must be a low light optical illusion - something to do with different sensitivity in center of eyes vs peripheral. Will try again in the daytime.

Need some interesting optical illusion type of posts on HN!

For those reporting scores: please also report device type, like LCD/OLED, or which phone model if applicable. Tweakers.net has a large database of screen color measurements. As mentioned in e.g. https://news.ycombinator.com/item?id=43746400, it can make quite a difference

My 18 score was on an Oppo Reno8, the 16 score on the not-known-bad screen is some ~2008 display. On the former, Tweakers reports an average color error of 3.42 ΔE2000, 9.58 ΔEITP, or 2.60 ΔE2000 if white is excluded