[HN Gopher] Too Much Color
       ___________________________________________________________________
        
       Too Much Color
        
       Author : maguay
       Score  : 132 points
       Date   : 2026-03-18 02:28 UTC (3 days ago)
        
 (HTM) web link (www.keithcirkel.co.uk)
 (TXT) w3m dump (www.keithcirkel.co.uk)
        
       | cratermoon wrote:
       | What's My JND? 0.0089 Can you beat it?
       | https://www.keithcirkel.co.uk/whats-my-jnd/?r=A30iKP__7_Hb
       | #WhatsMyJND
        
         | cafebabbe wrote:
         | Only with chrome devtools :)
        
         | xiconfjs wrote:
         | What's My JND? 0.0032 Can you beat it?
         | https://www.keithcirkel.co.uk/whats-my-jnd/?r=AUEjKP___831
         | #WhatsMyJND
         | 
         | I need a better display for sure :)
        
         | WalterGR wrote:
         | Discussed here: https://news.ycombinator.com/item?id=47321188
         | 
         | "Show HN: What's my JND? - a colour guessing game" 54 points |
         | 8 days ago | 62 comments
        
         | tgv wrote:
         | I'm color blind, and not even a little bit, but I scored
         | 0.0084. I've noticed before that my perception of contrast is
         | slightly better (than that of the people I ever compared it
         | with; admitteldly, that's only a handful, but they weren't
         | colorblind).
        
         | footydude wrote:
         | 0.0042 apparently https://www.keithcirkel.co.uk/whats-my-
         | jnd/?r=AaYkKP___-u-
         | 
         | There's was 2 or 3 where i had no idea, guessed and was a way
         | off.
         | 
         | There's was 1 where i did a hail Mary and got it. It was
         | interesting how some even towards the end were really obvious
         | and others were really subtle - I'd say I did better with
         | purple tones and worst with the blue / greys.
        
         | Jensson wrote:
         | That mostly depends on the quality of your screen.
        
           | giraffe_lady wrote:
           | It depends on something about your screen at least. I first
           | did it on a low quality monitor and it made the line between
           | the two obvious even if I couldn't tell the colors apart. The
           | "hard mode" one was impossible on that screen however.
        
         | halflife wrote:
         | 0.0021
        
         | bee_rider wrote:
         | .0037. IIRC it is possible to get a better score by looking
         | around the screen, your peripheral vision might be somehow more
         | sensitive.
         | 
         | I can see what they mean about .02 though. If I weren't
         | specifically looking for difference that's where the colors
         | become less noticeable.
        
           | majormajor wrote:
           | Looking around if you have an LCD also helps compensate for
           | colors shifting off-axis.
        
             | cyanydeez wrote:
             | What youre doing is seeing changes limited to one of the R,
             | G, B so instwad of judging integral xolors, your doing 3
             | different. The article explains how errors propagate, and
             | those RGB pixels will all shift errors because of matetial
             | science.
        
         | rXwubXUGAm wrote:
         | I got a 0.0035. I'm on a Dell U2724D monitor which is supposed
         | to have decent color accuracy and I cranked up the brightness
         | and contrast to a maximum so I'm sure that helped a somewhat. I
         | also noticed squinting and closing my eyes for a bit sometimes
         | helped when I felt stuck.
         | 
         | "Genuinely remarkable. You sailed past the theoretical human
         | limit like it owed you money. I'd accuse you of cheating but I
         | don't actually know how you'd cheat at this."
        
           | esperent wrote:
           | 0.0032
           | 
           | I'm on a Vivo X300 pro in a dim room, max brightness. Some of
           | these looked impossible but then suddenly I'd see the line.
           | 
           | https://www.keithcirkel.co.uk/whats-my-jnd/ #WhatsMyJND
        
             | drcongo wrote:
             | Same score here on my MBP with an absolutely filthy screen.
             | Reckon I could top the leaderboard if I cleaned it.
        
               | krsw wrote:
               | Same score and setup. Overhead lights were messing with
               | me a bit as well as the vignetting in the browser. I
               | wanna get sub 0.0030 now
        
           | rXwubXUGAm wrote:
           | Replying to myself. I also tried this with both my Samsung
           | S25+ phone and LG G5 TV and repeatedly scored in the
           | 0.003-0.005 range on both so it doesn't seem like the display
           | makes that much of a difference for me.
        
         | e1ghtSpace wrote:
         | 0.0043, but to be honest, I could probably do better if I
         | changed my monitor's settings. But I have it setup with low
         | brightness for night time lights off viewing that won't wake me
         | up.
        
         | foobarian wrote:
         | 0.0021. I find it helps to bob your head around like when you
         | are watching your food in the microwave
        
         | kalaksi wrote:
         | https://www.keithcirkel.co.uk/whats-my-jnd/?r=AG4mKP____6_
         | 
         | "This shouldn't be possible. I'm not saying that you cheated,
         | but not not saying that."
         | 
         | 0.0011. The quote seems a bit hyperbolic. There were maybe 2-3
         | that I didn't see and missed. 1-2 that I didn't hit perfectly
         | but close enough. Display probably affects results (but didn't
         | change any settings for this). I have a Dell IPS. I also moved
         | my head around a bit, felt natural while trying to discern the
         | colors.
         | 
         | I do have a good vision (including color). Reminds me of the
         | other color-game where you order some colored boxes to form a
         | spectrum.
         | 
         | Edit: just tried hard mode and got 0.0084. Missed maybe 3 that
         | I couldn't see. Usually some magenta or blue colored. Grey and
         | red / brown seem to be the easiest.
        
           | tstrimple wrote:
           | I got the same results you did. I think this is testing our
           | monitors more so than our eyes. Given the forum we're on, I
           | expect far better than average display devices being used
           | which could help explain why basically everyone is doing far,
           | far better than "average" according to the site.
        
         | kirillcool wrote:
         | 0.00057 here - https://www.keithcirkel.co.uk/whats-my-
         | jnd/?r=ADonKP_____7
         | 
         | I do work with colors pretty much every day as a UI engineer
        
         | tracker1 wrote:
         | I'm afraid to find out at this point... retinal damage combined
         | with cataracts that I'm waiting to have a job with medical
         | insurance to take care of... I used to be in the top 0.001% for
         | color detection, now I know I'm very far from it. Especially
         | towards dark and light brightness.
         | 
         | In the early 00's, I used two pro grade NEC flat panel
         | monitors... they weighed a lot... my desk at that time had a
         | permanent bow in the middle. It was around 2008 or so when I'd
         | moved them a few times in a year and a half and decided to
         | switch to flat panels... It became very clear to me around that
         | time, that most people really didn't care about color accuracy
         | in designs. Couldn't tell you how often I'd get "it doesn't
         | look like our printed logo" only to adjust their monitor
         | settings and voiala. Even then.
         | 
         | LCD flat panels are much easier to move around without killing
         | your back. OLED is pretty amazing, but I've got to turn my
         | brighness down a bit to make it tolerable... and I just about
         | have to use dark mode. But there aren't many options in the 45"
         | 3440x1440 display range, which is where I'm most comfortable
         | today.
        
         | jaen wrote:
         | Was fun and kind of meditative locking in like that - I noticed
         | that the anti-glare coating on my screen introduces a visibly
         | larger D than the later stages of the game (kind of a dithered
         | "cloud" noise), making it quite a challenge. _0.0021_ oneshot.
        
         | Tempest1981 wrote:
         | "At this rate, CIE will want your number" - the taunts are
         | great!
         | 
         | What's My JND? 0.0072 #WhatsMyJND
        
         | jcelerier wrote:
         | so basically this thread confirms that we're all getting worse
         | color that we can actually see because I guess of some terrible
         | lab measurement that got carried over like gospel? (0.0021
         | here, on a semi-cheap acer IPS screen)                   > At
         | its core this formula gives you a single number: how far apart
         | two colours look. 0.0 means identical, 100.0 means you're
         | comparing black and white. The magic number to remember is the
         | "Just Noticeable Difference" (JND). For dE00, JND is around
         | 2.0. Below that, people struggle to tell two colours apart.
         | Below 1.0, basically no one can. So anything under 2.0 is
         | "close enough" and anything under 1.0 is "you're kidding
         | yourself."
        
       | rekabis wrote:
       | > The magic number to remember is the "Just Noticeable
       | Difference" (JND). For dE00, JND is around 2.0. Below that,
       | people struggle to tell two colours apart. Below 1.0, basically
       | no one can.
       | 
       | Except for a tetrachromat. Specifically, a strong tetrachromat
       | that has both four colour channels in the brain and a different
       | frequency on the fourth cone.
       | 
       | Who are, admittedly, hella rare. Apparently there are less than a
       | few dozen confirmed world-wide.
       | 
       | But they do exist.
        
         | snarkconjecture wrote:
         | Computer screens have three-dimensional color spaces.
         | Tetrachromacy doesn't change that.
        
           | tgv wrote:
           | Is that so? Our color perception is weird. It's one dimension
           | split in three overlapping sectors. Adding a fourth sector
           | may add information that makes it easier to distinguish
           | colors.
        
             | Jensson wrote:
             | We do have four sectors, 3 color perception and then the
             | brightness perception that is used in the dark. In mid
             | darkness you get a mix of all of those, although the fourth
             | is not really perceived as a color so it can be a bit hard
             | to use.
        
               | tgv wrote:
               | Brightness is another dimension, not a "sector" (as I
               | dubbed it) on the color spectrum. But it would be equal
               | for all subjects in a test, so it can't add information.
        
             | giraffe_lady wrote:
             | Something I think about often is an oliver sacks book about
             | an ethnic group that has a particularly high rate of true
             | monochromacy. And the people with no color perception at
             | all are particularly adept at spotting certain plants based
             | on some characteristic of their leaves that is obscured by
             | color. So even removing information can change perception
             | in surprising ways.
             | 
             | OTOH sacks seems to have fabricated a lot of shit over the
             | years so who knows if this is even real. Another thing I
             | think about a lot now.
        
           | Zardoz84 wrote:
           | And the eye cones not are sharp filter, they overlap ranges
           | with mid-low sensibility. That must be nought to someone with
           | Tetrachromacy to percibe something different on a RGB screen.
           | 
           | > More precisely, she had an additional cone type L',
           | intermediate between M and L in its responsivity, and showed
           | 3 dimensional (M, L', and L components) color discrimination
           | for wavelengths 546-670 nm (to which the fourth type, S, is
           | insensitive). Source: Wikipedia
        
         | xyzsparetimexyz wrote:
         | > But they do exist
         | 
         | Do they?
        
           | IAmBroom wrote:
           | Do you doubt genetic and microbiological science?
        
             | rerdavies wrote:
             | Sometimes.
        
         | lucideer wrote:
         | > _admittedly, hella rare. Apparently there are less than a few
         | dozen confirmed world-wide_
         | 
         | What's actually hella rare is _tests_ for tetrachromacy. Given
         | the total number of people who have ever taken such a test, I
         | think it 's reasonable to assume there are significantly more
         | than a few dozen actual tetrachromats out there.
        
           | mark-r wrote:
           | It's theoretically related to color blindness, so you'd
           | expect it to be as common. But the problem is even if your
           | eye has the extra primary, your brain may not have developed
           | the ability to "see" it. They had to test quite a few people
           | with the proper genetic background before they finally found
           | one.
        
         | altairprime wrote:
         | Thanks to a genetic variation I have a variation that may be
         | similarly useful. I aced the JND test without contacts and with
         | adaptive white balance enabled, and I already know from playing
         | I Love Hue that my fidelity and velocity improves when I have
         | stereo vision.
         | 
         | It turns out that my left and right eyes are skewed apart along
         | a magenta/cyan axis. Left is more cyan, right is more magenta.
         | It's not as strong an effect as 3d glasses, maybe no more than
         | a 1-2% light gel, and under normal circumstances I mostly don't
         | notice it unless I'm doing color matching work.
         | 
         | If I try to do color matching with one eye, it's boringly fine
         | - 0.0022 JND, same as everyone else above. I'll get some things
         | slightly wrong as usual, in patterns that make sense for the
         | hue shift.
         | 
         | But when I use both eyes, the binocular process that leads to
         | 3d vision also locks on to color differentials as well as
         | spatial, and synthesizes imaginary color gradients out of flat
         | surfaces diagonally from contrasting corner edges. It's not a
         | problem for writing on paper or anything, but if you give me a
         | grid of flat paint chips I can order them by hue because their
         | gradient depths are wrong -- like, the whole sort by hue in 2d
         | grid thing is just "equalize the difference vector intensity
         | across the vector field" and that's a nice relaxing thing to
         | do, right? In essence, it's sort of like MIMO 3x2 vs. normal
         | vision's 3x1 or tetrachromacy's 4x1.
         | 
         | I know this isn't true 4x1 tetrachromacy because I discovered,
         | through the video game Intake (in which I reached 10th place on
         | the world leaderboard), that my ability to snap-differentiate
         | color is considerably more error prone when the two colors are
         | the exact hues of magenta-cyan that my eyes differ by. Which
         | makes sense: those would be my _lowest_ fidelity colors,
         | because they have the least distance from the differential
         | centerline, so trying to figure out which eye to use causes
         | little stutters in my color parsing and more frequent errors in
         | outcome. If it was "the same tetrachromatic in both eyes" I
         | wouldn't have trouble telling magenta and cyan apart, because
         | I'd have a fourth receptor with which to detect R /B vs G/B
         | shifts easily by their B/T difference.
         | 
         | I'm not sure if this is a normal circumstance or not, but since
         | my vision is extremely bizarre (-5 left, +2 right) and I can
         | function and drive _without_ eye correction due to forming
         | partial stereo depth out of blurry hue fields from the left eye
         | and telescopic light fields from the right, I think that
         | growing up without eye correction forced my brain to use hue
         | matching to stabilize my visual field in the absence of the
         | usual higher-fidelity "both eyes have the same focal plane"
         | convenience that most people have. And my depth perception
         | remains to this day extremely flawed; it works, enough that I
         | can drive with absolute precision, but I can't catch a thrown
         | object for crap and I occasionally parse 2d shapes with
         | contrast interplay as 3d shapes and then realize a moment later
         | that there is no 3d shape there -- painted lines on a
         | particularly damaged bit of road might at first blink read as a
         | curb -- b /c my depth perception was formed by prioritizing hue
         | and contrast at a reflexive level.
         | 
         | There's probably a formula somewhere that I could use to
         | calculate the theoretical boost in hue SNR by modeling two
         | towers, each with tri-frequency radio receivers with slightly
         | offset frequencies, and then calculating the net boost effect
         | of frequency trilateration across a spectrum for radio signals
         | of different frequencies. Someday I hope learn enough about
         | radio to document that and prove where my nodes of _worsened_
         | acuity are! Not that it much matters, but what a fun test it
         | would be.
        
       | sophieraiin wrote:
       | Am I pretty?? (story)
        
       | jacknews wrote:
       | lol, the website reminds me of tropes like the professional
       | cleaner whose house is messy, the chef who eats instant noodles
       | at home, or the haut couture fashion designer who only wears
       | jeans and tees. The colour expert whose website is monochrome.
        
         | olejorgenb wrote:
         | My impression is that they are a compression expert, not a
         | color expert. Make sense they chose uniform flat colors :D
        
         | chuckadams wrote:
         | "The cobbler's children have no shoes."
         | 
         | Maybe he understands the field so much that he prefers to
         | exercise it minimally in his hobby. Or maybe he just can't
         | decide. It also makes perfect sense for a study in colors to be
         | against a neutral background.
        
       | termwatch wrote:
       | interesting approach!
        
       | bhaak wrote:
       | He's talking about minifying CSS colors and I'm not sure if it is
       | what I think it is.
       | 
       | Do CSS minifier really adjust the colors in the CSS files to get
       | better compression rates or to reduce the number of rules in the
       | CSS?
        
         | altairprime wrote:
         | The author's minifier _now_ does so, yes. I think you'd have to
         | research further to decide if they're the first to do so or
         | not.
        
         | sheept wrote:
         | It depends on the minifier (SVG optimizers do this too), but
         | yes, they may reduce the precision of colors. I checked and
         | esbuild will turn lab() into a hex color if possible.
        
       | s1mon wrote:
       | This is an amazing deep dive into color difference measurements
       | and how sensitive the math is. The idea that we really need to
       | save characters - bytes - in CSS when we have so many web sites
       | chewing through 49 MB with the enshitification of the web is hard
       | to reconcile.
       | 
       | https://news.ycombinator.com/item?id=47390945
        
       | Theodores wrote:
       | Ahhh, NASA numbers! My favourite, particularly in SVG files, and
       | more recently in colours.
       | 
       | What is a NASA number?
       | 
       | Allegedly, within NASA, there is only a need for so many decimal
       | places. If I can remember correctly, nine digits would get a
       | spacecraft to land within a metre on the rock formerly known as
       | the planet Pluto. So no need for that, unless you are going to
       | 'occupy Pluto', building a few AI datacentres there.
       | 
       | In the context of SVG, usually it is icons that I encounter,
       | where the artworker has exported something like a search icon,
       | which is a circle and a line. These can be specified in SVG using
       | integers, and single digit integers, if you really want, but
       | let's make it two digits.
       | 
       | However, does the SVG file from the artworker have a viewbox
       | containing a circle and a line? Nope. Instead you get one circle
       | for the outer part of the circle in black and another smaller
       | circle in white. Oh, and a line. The circles will be written as
       | polygons with about two hundred vertices, with all vertices
       | specified with NASA numbers (as I call them), typically six
       | decimal places.
       | 
       | As a consequence, the file, which should be six lines of human
       | readable code balloons to many kilobytes of nonsense. Yes, this
       | can be put through SVGO but that will just remove some decimal
       | places and make the file even less human readable.
       | 
       | As a developer, the simple file is great as the inevitable
       | adjustments can be applied easily, maybe to make the icon bold or
       | to adjust alignment within the viewbox. However, when given
       | artworker files with NASA numbers, I then have to raise a ticket
       | so that I can get the corrected file two weeks later from the guy
       | sat in front of a massive Apple monitor with headphones welded
       | on.
       | 
       | The reason for not using NASA numbers has nothing to do with
       | bloat, as no optimisation will make up for the mountain of
       | javascript the marketing guys have bundled into their Google Tag
       | Manager, it has everything to do with efficient workflows.
       | 
       | Generally the customer does not care about fonts, colours and
       | much else that designers fret over. If we went back to the 216
       | 'web safe' colours of yesteryear (for CSS, not images), would
       | anyone notice? If we could not load custom fonts, would most
       | people notice? They might, but this would not prevent them from
       | surfing the web.
        
         | rerdavies wrote:
         | Good design speaks to credibility, with some justification. If
         | somebody doesn't care about whether their webpages look good,
         | it suggests that they also didn't care about whether their
         | content was accurate.
        
       | Sharlin wrote:
       | Eight bits of precision should be enough for everybody.
       | 
       | (It both is and isn't, depending on the use case, but I'm pretty
       | sure nobody's design needs to make a difference between #123456
       | and #123457.)
        
         | kg wrote:
         | For gradients it definitely isn't unless you have the ability
         | to do FRC dithering where the dither pattern changes every
         | frame. The banding is very noticeable on a large enough screen.
        
         | marcosdumay wrote:
         | Yes. The claim that you don't need more than 3 decimal places
         | is laughable. Your artificial design doesn't need decimal
         | points. At all. You probably can do even better by ignoring the
         | last 4 bits completely.
         | 
         | That said, the article is very interesting, and that claim
         | applies on different contexts. It's just aimed at the wrong
         | one.
        
       | taeric wrote:
       | This reminds me of the amusing tendency of people to use the full
       | double for recording lat/long of locations.
        
         | xigoi wrote:
         | https://xkcd.com/2170/
        
           | skyberrys wrote:
           | "You're pointing to waldo on a page" ... There's always an
           | xkcd.
        
         | pezezin wrote:
         | It depends on your use case. Storing WGS84 coordinates as
         | 32-bit floats can incur on errors of several meters. It might
         | be good for your fitness tracking application, but not for
         | serious GIS usage.
         | 
         | Case in point: many years ago I was working on some software to
         | generate 3D models from drone pictures. The first step of the
         | pipeline was to convert from WGS84 to ECEF
         | (https://en.wikipedia.org/wiki/Earth-centered,_Earth-
         | fixed_co...), an absolute Cartesian coordinate system. Well, it
         | turns out that at the scales involved, 6.371 million meters,
         | 32-bit floats have a precision of half a meter, so the
         | resulting models were totally broken.
         | 
         | Moving to 64-bit floats fixed this issue.
        
           | taeric wrote:
           | Isn't that more of using a float to represent the number?
           | Would be akin to trying to represent .5. Which, if your goal
           | is to represent decimals, you are best off not using floats.
           | 
           | Granted, just storing it as a 32 bit integer is probably
           | difficult for most uses. BCD just isn't common for most
           | programmers. (Or fixed point, in general.)
        
             | pezezin wrote:
             | If your goal is just to store the coordinates in a
             | database, sure, use fixed point or whatever.
             | 
             | But any kind of calculation will involve a great deal of
             | trigonometry, square roots, and the like. It is just easier
             | to use floating point. Examples:
             | 
             | https://en.wikipedia.org/wiki/Geographic_coordinate_convers
             | i...
             | 
             | https://en.wikipedia.org/wiki/Vincenty%27s_formulae
             | 
             | https://gist.github.com/govert/1b373696c9a27ff4c72a
        
       | quantummagic wrote:
       | Very interesting article, and the color picker is exceptionally
       | revealing. As for the challenge, it stopped working in Firefox
       | after the first half dozen examples; but on Chromium I got a
       | decent .0042 Fun!
        
       | cmovq wrote:
       | I've always assumed minifiers were a kind of lossless
       | compression. I guess this optimization makes it lossy? Even if we
       | can't tell the difference between oklch(0.659432 0.304219
       | 234.75238) and oklch(.659 .304 234.752) they're still different
       | colors.
        
         | cyanydeez wrote:
         | Tge whole contexr of the article is answering your question: a
         | "different color" is a specification laden structure and the
         | answer is no according to spec.
        
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       (page generated 2026-03-21 23:01 UTC)