But another problem is with displaying the colors essentially full-window, which is going to be nearly-full-screen for many users. When we're staring at a screen with a particular tint, our eyes quickly do "auto white balance" that skews the results. It's the mechanism behind a bunch of optical illusions.

To address that last problem, I think the color display area should be much smaller, or you should be shown all hues at once and asked to position a cut-off point.

1. If two people take the test with the same device, in the same lighting (e.g. in the same room), their relative thresholds should be fairly stable. 2. If you average over large populations, you can estimate population thresholds, marginalizing over monitor calibrations.

The most interesting thing for me is that while cyan (#00ffff) is nominally halfway between blue and green, most people's thresholds, averaged over monitor calibrations, imply that cyan is classified as blue. I was not expecting that the median threshold (hue 174) would be so deep into the greens.

There are also other cultures, such as Russia, where light blue / dark blue (simplification) are effectively considered separate colors.

All this to say, personally, I think we will continue to evolve to recognize more distinct "colors" such as teal, which is neither blue nor green but somewhere between. A lot of this recognition power is rooted in linguistics and culture, it's not as strictly biological as one might think.

> Russian does not have a single word referring to the whole range of colors denoted by the English term "blue". Instead, it traditionally treats light blue (голубой, goluboy) as a separate color independent from plain or dark blue (синий, siniy), with all seven "basic" colors of the spectrum (red–orange–yellow–green–голубой/goluboy (sky blue, light azure, but does not equal cyan)–синий/siniy ("true" deep blue, like synthetic ultramarine)–violet) while in English the light blues like azure and cyan are considered mere shades of "blue" and not different colors.

> Blue: plava (indicates any blue) and modra; in the eastern speaking areas modra indicates dark blue, in some of the western areas it may indicate any blue

etc. from https://en.wikipedia.org/wiki/Blue%E2%80%93green_distinction...

I am not deeply knowledgeable on Russian, I failed Russian in high school, just going off of my surface-level knowledge of linguistic relativity regarding color, and discussions with a friend from that part of the world, so I might not know what I'm talking about here.

An individual person's answers on this kind of question are likely to vary from day to day, are context dependent (i.e. whether one object or another appears more "green" or "blue" depends on what kind of object it is), and colors this intense are very sensitive to changes in eye adaptation and technical details of the display and software, as well as inter-observer metamerism.

So in addition to the color naming difficulties, it's not even a very good test of color naming, if you want to get reliable psychometric/linguistic data.

I am not afraid to say this is poorly designed.

I wouldn't describe teal as blue or green any more than I'd describe purple as red or blue, so being forced to pick felt silly. Like being forced to choose my seventh favorite Norwegian glacier - technically its a valid question but my answer is necessarily going to be arbitrary.

I would actually find it more practical to determine the thresholds on both sides where I find it to become ambiguous.

So how could the point of this exercise possibly be to find the range of ambiguity?

It lacks the "can't classify" to make it a better tool.

I bet if the choices actually said "This is more green than blue" the results would be different.

Or people will naturally intuit that they should choose whichever answer they think is closer to true.

I'm talking about random day to day browsing when you stumble on something random on the internet.

Taking how you behave, and extrapolating that it to everyone, (and furthermore being unable to accept that other people might behave differently), is not a winning strategy for life.

It's clearly more turqoise than blue. Or green.

Turqoise on a computer monitor is always missing part of itself, so maybe I should've answered based on that, but I don't think the computer monitor was the point.

(Yes in New York and Indiana, no in Massachusetts, and the law is silent elsewhere. Personally I believe that because the torta exists, the burrito may have some characteristics of a sandwich but should be considered a wrap)

When I could see the entire gradient, I actually thought green continued to the right a bit more than where my line was.

Ooh maybe have the user slide a gradient left and right inside a window, aligning the center of the window with where they think the line is between blue and green (i.e., instruct the user to fill the window with equal amounts of green and blue).

Does it not actually work on mobile?

Perceptually (that is, in CIE-LCh color space, for example), the hue component of #00ffff is a lot cloer to #00ff00 than it is to #0000ff. But the website doesn't ask which color is closer, it asks if it's "green" or "blue". And how we use those words has more to do with culture than with perception. We also call the color of a clear afternoon sky "blue", even though that is perceptually extremely far away from #0000ff.

Yes, because (at least for me) the thought went "well that's cyan, it's not really blue but if forced to pick, cyan is more like blue so I'll click that". It's like rounding up at 0.5.

That's what I'd do if I were being paid to take the survey. Instead I just closed the window as soon as it popped up cyan and only gave me blue and green as options.

I used my phone on a mount, and completed the test with my wife, children and myself - I was interested (though not surprised) what an outlier I was, as I am colour blind in various combinations, but though my wife scored 'bang in the middle' - it was interesting that wasn't common.

My kids were both to the left of the scale fwiw - I was further right than 98% of people.

RYB, being taught in grade school, has a lot of influence on how people perceive and name colors, which is what this conversation is about.

I would hope that here on HN, people are aware of RGB primaries, and then maybe CMYK. Saying that cyan is "not primary or secondary" is just wrong. Even Wikipedia explains in the first paragraph that the RYB model has a "lack of scientific basis":

https://en.wikipedia.org/wiki/Primary_color

Similarly, "magenta" is a poor name to use for #ff00ff. The term "magenta" is a jargon word for the slightly purplish printer's red, which was chosen to avoid confusion with the English word "red". It has a completely different than the equal mix of RGB R and B primaries.

("Red", "green", and "blue" are also very poor names for the RGB primaries, which are substantially orangish red, yellowish green, and purplish blue.)

You're not asking gender of the test taker. Your results will be skewed because you're probably getting more men than women. Women in general have more ability to detect green vs blue.

It could be a high enough percentage to make the results from this site noticeably different between the sexes.

Primary Additive Colors: Red, Green, Blue

Primary Subtractive Colors: Cyan, Magenta, Yellow

But, before digital color displays became popular, the average person had, by far, mostly exposure to subtractive (paint) colors.

US school children are taught from birth that the primary subtractive colors are red, yellow, and blue, simply because those words are easier to pronounce, and so magenta is a weird "red" and cyan is a weird "blue" , until the children discover on their own, or in specialized print/paint schools, red and blue are not primary subtractive colors.

Humans are terrible at naming things.

And to bring it back to Current Thing: Google AI cites this source for its red/yellow/blue claim, even though explicitly this source says that Google gives the wrong answer.

https://science.howstuffworks.com/primary-colors.htm#:~:text....

Will GenAI's aggressive ignorance kill sarcasm and nuance in writing? Or will people learn to ignore AI input like they ignore banner ads?

for differentiation of blues?

I remember reading that modern Greek has two color-names for sky- and dark- blue (not sure what the prototypes are for each nor if they have hue components, maybe the "sky" blue is green-shifted?)... always been fascinated by the discussion of "weak Sapir-Whorf" around this and would be quite interested to see if there are any differences in discrimination...

The classic cognitive/perceptual psyche data to gather would be time-to-discriminate, with the prediction being that Greek speakers make faster judgement because they have higher/faster discrimination, than others.

Not sure how you'd pose the question to non-Greek speakers tho :)

This might be one case where it might make sense to cluster between the reported operating system. At the moment I only have a family of Macs to test, but I can imagine that Windows users with their different default gamma get back different results.

I kept pressing green until the end because you had no 'cyan' button to press when clearly many colors were actually cyan. Cyan is not blue.

Incidentally, my color vision is perfect on all Ishihara tests.

Cyan is not. The author decided to cut off the colors list at secondary colors. There is nothing wrong with that.

'The author decided' is not physics. Suggest you look at the Wiki page under 'Wavelength': https://en.m.wikipedia.org/wiki/Color_vision

Green: 500 - 590nm, Cyan: 485 - 500nm, Blue: 450 - 485nm.

Color vision theory is far too complicated to discuss here, and I'm not going to debate cyan as a mixed color of blue and green wavelengths versus a fixed wavelength that's in between both of them.

What the author provided was, at best, misleading but nonsense as far as science is concerned.

If the author said he was an artist and presented colors as a preferential list it would have been a different matter.

BTW, I don't mind being voted down (it happens to me regularly), but here those who did are only showing their ignorance. I'd add the author—who penned here—ought to explain his actions in much more detail.

Not necessarily because the ambient light would affect the screen shows (it's emissive, not reflective) but because the brain also does "auto white/colour balance".

For a fun experiment, get your hand on some heavily yellow-tinted party glasses, go outside on a clear day with a bright blue sky.

When you put them on everything will be stark yellow tinged (and the blue sky will be completely off, like green or pink, can't recall which) but after a little while going on your business, perception adjusts and only a much less dramatic yellowish veil is in effect. You'd look at the sky and see almost-blue.

The kicker is when you remove the glasses: the sky will suddenly be of a glorious pink! (or green, can't recall) Only moments later it'll adjust back to be blue.

A certain wavelength may be absolute blue of a certain kind, but the perceptual system is all relative: "wait, I know this sky should be blue because that's what I've always seen, so let's compensate".

The same kind of effect - although less dramatic - can be achieved with lights that can be adjusted from say 2400K to 6500K and having as reference an object that is known "pure white", like a A4/letter sheet of paper.

This effect, in turn, adjusts how "absolutely displayed" colours are identified by way of biasing the whole perceptive system. AIUI that's the rationale behind Apple's True Tone thingy, aiming to compensate for that.

So the result of this test should be somewhat different depending on ambient lighting temperature.

No idea what "AUIU" is, but yes, generally displays should do automatic white balance like iPhones do. I don't know why most Android phones don't seem to do it (pretty sure mine doesn't), and generally TVs/monitors also don't do it. (The required color temperature sensor can't be that expensive?)

The rageguy one would say either patents or "whoa the colors really pop I want that shut up here's my $$$" uncancellable LOOKATMEIAMTHESHINY mall mode, but via Occam'r razor I think mostly because they (manufacturers) simply don't care (about consumers, or about making a good product at all)

TVs/monitors (or laptops even, and more phones that you'd believe) with just a simple auto-brightness are stupendously rare even though Apple does it since forever and a half ago.

Android does have a night mode which changes the white balance of the screen at sunset and sunrise, but this is just a binary thing and doesn't respond to actual ambient light.

  > Ambient light will also affect the result.

In order for it to be a true "neutral" test, each test would need to be preceded by a "palate-cleanser" gray screen, or something, and there would probably need to be a neutral border.

> you should be shown all hues at once and asked to position a cut-off point.

This is actually the way I have seen this stuff tested, before.

UK Costco hotdogs are £1.50, which is not equal to $1.50, reflecting both its arbitrary nature and that UK purchasing power is weaker than the exchange rate would appear. (Computer books are a frequent offender here of having the same $ and £ prices)

If you're doing this on a phone, try holding your phone at arm's length and against a white background (such as the wall or ceiling) and doing the test that way. Assuming you have redshift/night mode disabled, I suspect you'll end up closer to the median.

I always forget how much white-balancing my vision does.

Whether its a dark room or sunny kitchen, i'm not sure whether Turquoise is ever going to be blue or green. The entire question seems more like wordplay.

Edit: Possible improvements: changing the wording to "this is MORE green" and "this is MORE blue" and randomizing the order in which they are shown, somehow. I realize you're just doing some kind of binary search, narrowing the color range.

This is not to mention color calibration of your monitor, or your eyes adjusting / fatiguing to the bold color over time...

It of course depends on the calibration of your monitor. One of the reasons I did this project is I wanted to see if there were systematic differences in color names and balance in the wild, for example, by device type (desktop vs. Android vs. iPhone), time of day (night mode), country (Sapir-Whorf), etc.

It might work better for me to do some contrastive questioning: show a definite green followed by an intermediary color, then a definite blue followed by an intermediate color.

See it as a way to avoid perceptual hysteresis.

With the third colour, I just thought "no, that's teal", and my decision was (as you suggested) semi-arbitrary.

I don’t think that forced choice can give accurate results if a substantial number of people perceive green and blue as being non-adjacent - i.e. there exists a color between green and blue (turquoise/cyan/teal).

Otherwise it’s like asking people whether a color is red or yellow, when it’s clearly a shade of orange.

Orange is closer to green than blue but I wouldn’t say that it’s a shade of green. It’s just orange.

Your website is not talking about "levels" of colour.

It's asking "is this blue or green", not "is this closer to blue or closer to green".

The question (1) "is this blue or green" has three valid answers: blue, green or neither.

The question (2) "is this closer to blue or green" only has two valid answers.

I would assume that with these types of surveys, the first thing to do is to qualify the proper categorization of the question.

Sorry to say, but to me it seems that almost all of the confusion in the discussion here is because you're asking question (1) (which has three valid answers) but expecting an answer from (2) (which indeed has two valid answers).

And the teal that I referenced in my earlier comment was (for me) such a colour.

Maybe if I'm given two colors inside that range, I can say which is bluer and which is greener. Given just one color, I simply cannot say that it's green or blue, or even if it's more green than blue or vice versa.

I stopped at the 3rd or 4th come because I couldn't give a honest answer. That makes the test useless. I can't complete it with correct answers, and if I give incorrect answers, the conclusion is useless.

There were two distinct points, one for blue and one for green, where my mind would place the transition to the colour in between.

(And yes, on one end it's bluer and on the other end greener, but (much like a shade of orange is neither red nor yellow) the colours are still not either green or blue.)

And (even if I could) a bluish teal would no more be a blue than a reddish orange a red.

I think I can get over it, but it requires conscious effort and even then, who knows. Bias is often unconscious.

Another possible improvement would be to alternate the binary search colors with some randomly-generated hues. Even if those answers are outright ignored, and the process becomes longer, I think they would help to alleviate that bias. At least you wouldn't be directly comparing to the previous color.

However one of the key people that built our colour pipeline was also colour blind, so its not actually a requirement, so long as you use the right tools.

Most people aren't that sensitive to colour, especially if its out of context. a minority of people aren't that good at relative chromaticity as well (as in is this colour bluer/greener/redder than that one) But a lot of people are.

Language affects how you perceive colour as well.

But to say the experiment is flawed I think misses the nuance, which is capturing how people see colour _in the real world_. Sure some people will have truetone on, or some other daily colour balance fiddling. But thats still how people see the world as it is, rather than in isolation.

A modified version of the test that finds two boundaries (green/neither/blue) could be interesting.

Or maybe it just needs to take more samples, in a more random order.

I agree with you, the whole thing is flawed when it could be better. When you ask the question "is my blue your blue?", you are evoking the old philosophical question, and it's a question about color perception, not words. This test did not test color perception, it tested "what word do you use?"

I think of blue as a pure color, and green as a wide range of colors all the way to yellow, to me another pure color. so if there's any green at all in it, I'm going to call it green. (maybe it's left over from kindergarten blending "primary colors". also, while I like green grass, I don't like green as a color, so any green I see is a likely to make me think, ew, green) But in terms of what I see, I can only assume I'm seeing the same thing as everybody else is because the test is not testing it. Just because I call something green doesn't mean I don't see all the blue in it.

>Edit: Possible improvements: changing the wording to "this is MORE green" and "this is MORE blue" and randomizing the order in which they are shown, somehow. I realize you're just doing some kind of binary search, narrowing the color range.

yes, the test should show you pure blue, then a turquoise mix, then pure green, and a ... etc. It should also retest you on things you already answered to measure where you are consistent.

Show people a colour and map their brain activity - the level of similarity between two people's colour perceptions should be reflected by similarities in the activity.

One persons ‘blue’ activity could be different than another’s while still being the same wavelength of light and general perception.

It's a question of subjective experience - and that experience should be reflected in electrical activity.

Given the fact that the broad structure of the brain is largely shared across members of the species, similar stimulation should trigger similar activity in the same regions of the brain.

If the same colour triggers markedly different activities, it would not be unreasonable to conclude that the subjective experiences are not the same.

If I were to imagine a warrior, and his general perception of the colour red, I may find the way his brain processes the colour more closely to a rival warrior than his wife the gardener.

A real world example; London taxi drivers and bus drivers show distinct patterns of changes to the hippocampus.

https://pubmed.ncbi.nlm.nih.gov/17024677/

The way that the mapping data is stored will be heavily bias towards being spatially reflective of the real world counterpart.

Note the bias will be towards a degree structural isomorphism, one internal 2D + 1T spatiotemporal surface map of the city might be a rotation and/or reprioritisation of another - but they will have a shared basis (convergent compute simulations of biased subsets of the same real world structures), and when navigating from point A to point B, the path and nature(though not the propagation vector) of the electrical activity of both will be reflection of the same real-world surface map.

Now I say spatiotemporal - because the driver going from A to B in the morning will develop different expectations of the levels of traffic at different parts of the journey.

Or do you think fingerprints are the most random thing in humans?

There may be general patterns from above, but the actual details vary immensely when you zoom in.

Large populations may still roughly conform to a normal curve, but the volume under the deviations is still huge. And the dispersion is immense.

Honestly, it would be shocking if it were even a little true beyond ‘frontal cortex’ levels of granularity. And even then, Phineas Gage type situations make it clear that may not actually be required either.

And that means completely different individual activity can trigger similar subjective experiences as much as similar activity can trigger different subjective experiences, no?

Because the second color I saw was somewhat like turquoise and the site is called 'Is My Blue Your Blue,' I decided that everything that you say yes to colors would be blue and everything else would be green. I never saw a green until the result was displayed :D

FAQ:

* I can't know your monitor's calibration, your ambient light, or your phone's brightness. Obviously, this will affect the results. However, I am tracking local time of day and device type, from which we should be able to infer whether night mode and default calibration has any aggregate effects. Anecdotally, thus far, I haven't found any effects of Android vs. iPhone (N=34,000).

* The order is randomized. Where you start from can influence the outcome, but methodologically it's better to randomize so the aggregate results average over starting point. You can run the test several times to see how reliable this is for you.

* It's common practice in psychophysics to use two alternatives rather than three (e.g. blue, green, something in the middle). It would be a fun extension, which you can handle with an ordered logistic regression. The code is open if you want to take a shot at it: https://github.com/patrickmineault/ismyblue

* I will release aggregate results on my blog, https://neuroai.science

* I am aware of most of the limitations of this test. I have run psychophysics experiments in a lab on calibrated CRTs during my PhD in visual neuroscience. *This is just entertainment*. I did this project to see if I could make a fun webapp in Vue.js using Claude Sonnet, and later cursor, given that I am not highly proficient in modern webdev. A secondary point was to engage people in vision science and get them to talk and think about perception and language. I think it worked!

My partner and I were well aware of the limitations, but it has clearly demonstrated our difference in perceptions in a way we were both happy with. Being able to see where your partner lands relative to you is deeply satisfying.

I think my "blue" is a way more specific shade than most people (hue 192 here, whatever that means on an uncalibrated display). Likewise, I'll usually say "purple" before others.

So you've thought about that already :- ) (it's evening here)

If I were to call it blue or green, it would not only not be reflecting what I think, but I could not guarantee that if I'm show the exact same color again, that I will go the same way. So I felt there was no point in continuing.

This is a problem in the method; there needs to be a third choice, so that the user can always answer (at least if the test color is always in the blue-green gamut).

It could work with two choices if the user were instructed to randomly choose in the event of indecision. I mean, truly randomly, like by means of a fair coin toss. But that could just be implemented for them by a third button. That button could then just record their indecision rather than randomly choose between blue and green, so you have better data.

Without a third choice, or properly randomized behavior, you have bias problems. For instance, a certain user who likes the blue color might always say blue when not able to decide. Another one might always go for green. Yet, those two users might exactly coincide in what they unmistakably call blue, green and what triggers hesitation/indecision.

(I realize that no matter how many bins we have, there are boundary indecisions, like not being able to decide between green and blue-green. What range constitutes indecision is also subjective.)

To poke a whole in your analogy, a more apt comparison would be to a gradient of sweetness, where one can indeed describe a flavor as "more sweet" or "less sweet" relative to apples and bananas.

The thing I find being colourblind is that I value colour less than shade. Colour signals, even when I can tell them apart, are just less important to me than to non-colourblind people.

I most recently noticed this playing Valheim with my wife. There are red mushrooms in the game, surrounded by green foliage. I noticed that I have trouble spotting them, even though I have no problem seeing that they are red and the foliage is green. To her, the mushrooms stand out as being very visually different from the background and immediately noticeable. To me, they just aren't that distinct and get quite hard to spot.

So while I got the green/blue distinction to within 80% of the population, despite my shitty colour perception, it just didn't matter. At some point in the process I got to "I really don't care. I would ignore the signal that any further difference in colour is sending".

As you can guess, I have fascinating talks with designers and artists, to whom the differences really matter. I understand that colour is really important to them. I just don't see it.

To help explain our experience, it's like trying to distinguish between two similar shades of yellow. It'll be clear and obvious that both are the color yellow. When there's only one example of each standing next to each other, it'll be easy to tell which shade is the lighter one, even if it's only slightly different. But if you had a sea of examples and are asked to pick out which yellows are slightly lighter than the other ones, then it might cause you to stop and study them for awhile to figure it out.

It's just like that for the common forms of colorblindness (where the color cones in the eyes are bent, but not missing), but instead of this metaphorical "yellow" it's this special "red-and-green" color that we see that's different from what everyone else sees. It's like trying to distinguish between two different shades of the same color, where it's obvious which is which when there's only two examples to compare to but not so much when your entire field of vision has bits of one hidden amongst a sea of the other. It's like red and green are a spectrum of the same color rather than being two separate ones.

My mother was an artist, spent ages testing my colour range with a set of Pantone colour swatches, just out of curiosity rather than as an attempt to cure it. That's how I know I see shade better than colour - she would show me two swatches that differed slightly in colour and then two that differed only in shade (or shade/tone/tint to be accurate). I could tell the shade differences apart better than the colour differences.

So I'm not sure that early training would help. But it couldn't hurt

Fellow CVD person here, I have that same problem at work. That and when there are up/down arrows and whether up or down is good changes based on the metric and they use color to let you know. They all look samey unless I actually stare at them for a while and the color difference sorta bubbles up.

It's so annoying too because it'd be trivial to use different signals instead of color, but no one cares about the 1/12 of us that are colorblind. It's crazy that the ADA doesn't recognize CVD as needing accommodation when it's far more common than most other disabilities.

I'm pretty sure there's some hysteresis going on - if we randomly end up in the ambiguous zone on the bluer side, we'll be pressing "blue" every time a small change happens, because it's basically the same color. Until the changes add up so much that we're out of the ambiguous zone on the green side - and now our "border" is far on the green side. But if we started on the other side, entering the ambiguous zone from the green side, it'd take a big cumulative change before we press "blue".

I wonder if this has anything to do with your upbringing. I grew up on a farm in a dry part of Australia, where the grass didn't often get very green. Most of the year it was yellow. If you associate green with grass and the grass is yellow, maybe you associate green with a yellower colour?

Old Japanese traffic signals had blue tinted lenses, like ultramarine blue. Those lenses were used in conjunction with warm yellow incandescent lamps, technology available at the time. Deep blue + warm yellow = green.

Over time the green color must have normalized, without laws and slogans not reflecting that. And nowadays they're green LEDs.

In all rulebooks, lights are red-yellow-green, but in many places, I can see red-amber-turquoise. Now a sure way to get a traffic police officer livid is to call the yellow light “amber” or “orange”…

It's funny though - I feel like I'm less likely to go green on the other direction too. I'd probably say a tennis ball is right on the line, and seems more yellow than green to me too.

Maybe I'm some sort of green gatekeeper, and I don't want to dilute my personal definition with lesser greens. Green is my favorite color, I'd say, so maybe that's something to do with it.

I'm French and my boundary is at 167 apparently (though I have a poor screen and depending on where I look, I could say that even further towards the green side is still blue). But a regular occurrence at home is my wife (who speaks a different language, we don't live in France) talking about « the green table » while I'm trying hard to find any green table around us, until I realize she's talking about that turquoise table that I call the blue table. Also happens on the red/pink and pink/purple boundaries.