The "blacklist" parameter prevents that you get the same challenge twice. Note also that it submits every answer to the server (fine imo, but I think it would be even nicer if this was mentioned on the page)
Happy to hear, though note the file is without l (lowercase L) in the end (I guess autocorrupt is to blame here?). Fun fact: if you remove the filename, it'll show you all the crap in that directory, listing this file as being last modified in 2015-09-27. If past performance is an indicator, it should be stable to use for the next ten years as well :D
Thanks for posting, I thought the same thing... my (useless data point of one) results showed 100% accuracy except the last four, which I thought "wow, I am just guessing now, can literally not see a difference".
Got 18/20. I chalk that up to spending years as a graphic designer. I'd like to see a similar study about which text was perfectly kerned, or by how many pixels an element was off-center or misaligned. I can spot that on billboards a block away, and my life is therefore a constantly grating experience.
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.
Regarding the LED lights: unless you use a lamp with CRI < 90, you see obvious, glaring color distortions, and some colors just "disappear", cannot be seen, because of the lack of a particular spectrum bands. Sadly, most inexpensive LED lamps have CRI around 80, and that light feeld definitely artificial, even if pleasant to the eye. A lamp with CRI 90 is okay, most things look natural, even though you can notice it's not sunlight. A lamp with CRI 95 is very fine, it's practically sunlight, and most tricky colors are visible well. I've never encountered a lamp with CRI, say, 97, but they exist and cost a lot.
IME producing artwork that relies on subtle color relationships requires high quality, "full spectrum" illumination. Natural daylight is the obvious canonical option, but of course not always practical.
My studio gets very little natural light, so selecting optimum light sources is crucial. At one time the most practical option was D50 compliant fluorescent tubes, but these were only fairly acceptable.
Situation with LED lamps is also difficult. Even CRI 90 is inadequate, mainly poor red emission and excessive blue radiation. However D50 compliant LED fixtures are available if somewhat more expensive vs. typical LED lamps.
One vendor worth checking out is Waveform Lighting [0]. They offer several types of products with CRI 95 and CRI 99. I've been using their D50 'shop light' for several months and find it very satisfactory.
Surely an incandescent bulb, being a black body radiator, has a CRI of 100? Yes, the temperature is low compared to sunlight, but the rendering is theoretically perfect.
I suppose if you want to get closer to sunlight, you need a carbon arc, which is only a few hundred degrees cooler and again, a perfect black body emitter.
I got 19/20. Turned off True Tone and cranked the screen brightness. Half the time I didn’t know if it was just my eyes playing tricks on me, but it was interesting to notice how the colors seemed completely indiscernible for a few seconds and then suddenly one stood out.
I also got 18/20, I was confident on most of them, blinking I found "reset" my vision and made it easier. This was on my relatively comfortable (not too bright) monitor.
Yeah, metamers are a trip and a bad LED bulb will really screw with the appearance of colors. If anything, screens are more consistent, but more limited.
I wish this had a "I can't tell" option. A few of the really hard ones I got right, but I'd say it was more of a lucky guess than a genuine ability to discriminate the difference.
This is from the creator of the ScienceClic YouTube channel [0]:
“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!”
Would be interesting to get some basic analysis of my results. From a glance it appeared that the ones I missed (6) tended towards red. The low saturation ones and green ones I found to be easiest, but was there any actual significance of the distribution of my errors? Simply too small a set to say?
I got the same number wrong but I've passed every Ishihara test ever thrown at me. I did this test on a cheap mobile that's not calibrated, so it's anyone guess what its gamma and transfer curves are like.
One should only take such tests seriously if one's using a properly calibrated monitor and it's viewed under ideal viewing conditions.
17 out of 20. Was super easy until #10 and I had to stop and think more carefully (which was actually my first mistake), and then I got #14 and #15 wrong. The score was about what I expected, though - would've been surprised if it was <15 correct.
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?
There is certainly also a device limitation. I would expect that with less than full 24 bits of color, some fields might just look the same and the results do not depend on your vision any more.
Let's say the device has a "24 bit color display".
What about eye protection color shifting? This limits the color space used could reduce the effective remaining bit depth.
Or maybe they do temporal dithering to get more bit depth? Or maybe the 24 bits are already achieved with temporal dithering?
It does not need to be a calibrated display, but a cheap tablet in sunlight will be worse than a color grading monitor in a reference environment.
I hope they also register the devices used and analyze the statistics on that.
Calibrating a monitor is intended to ensure that colors on your monitor closely match colors on an ideal reference monitor. That's not the same thing as ensuring that two different colors on the same monitor actually show up differently; that's a much looser quality standard, because even a badly mis-calibrated monitor may still show both colors as distinct wrong colors.
I would only expect poor calibration to break this test for colors near the edge of the display's gamut, or if there's a drastic-enough shift that the color space's lack of perceptual uniformity means a numerical difference that should have been visible ends up in a different part of the color space where that same numerical difference is not perceptible.
What stood out a lot in this exercise is that when looking at, versus near a disc, its luminance (or maybe the color as well) is perceived as changing. Almost the same i have when staring at not too bright stars, they seem to disappear when staring directly on them.
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.
I experienced this too. IIRC the brightness-sensitive rod cells are more concentrated in your peripheral vision while your central vision has more colour-sensitive cone cells. This makes the centre of your vision less sensitive to dim objects, so you can see them only while looking indirectly (and they "disappear" when staring at them)
Another related effect is flickering of badly designed lighting only in my peripheral vision. When looking directly at the lights they look fine, but when the lights are in my peripheral vision they appear to flash distractingly. I think the peripheral vision is optimised to detect fast changes/movements. At least, that makes sense based on evolution.
The flickering i see as well when looking near my ali express outdoor LED light strip, from the corner of my eyes. The sub-components of the PWM seem to emerge as well.
I'm curious how the eye migraine is related. I had one many, many years ago. It was a smallish (palm at arm's length) oval in the center of my vision that looked like snow on an analog TV, accompanied by a feeling of overwhelmed by all the colors of the products on the shelves (I was in a grocery). It stuck around for about half an hour for me as well.
I've also had eye floaters which cause things to distort and can be hard to see through. For about 6 months I had a large one in the center of my left eye vision, which was a bit scary when I discovered I might not see a car reflected in my wing mirror.
I’ve had visual migraines ever since I started training hard with weights. Played sports in High School and never had one, but suddenly I’m doing CrossFit in my late 30s and an hour after a workout I get these sparkly jagged lines in my vision (both eyes!). It took a while to even be able to describe them, let alone figure out what they were. Thankfully there’s no pain and they clear up after a while, but I have noticed since this all started that I’m also a bit more sensitive to screen brightness. That HDR emoji article from the other day was kind of triggering.
I've had it happen many times and it's usually followed by a regular headache. Quite terrifying the first few times it happened to me. Felt like I was losing my sight.
Spending the whole night gaming when I was younger would sometimes trigger it in the morning. Thanks to not having any more time for that, it hasn't happened in years.
Similar experience. What surprised me: sometimes the odd-one-out was really quick/easy to see, and other times it took much longer & I thought "at the end, they'll say all disks were the same color".
For some of the easier ones, I was surprised by how aggressively my brain was making what seemed like "close" colors stand out. Like it was mentally "highlighting" the odd one out. I thought that was cool, but eventually the later ones were hard enough that the effect went away, and I was much less confident in my choices, and I got 3 mistakes, all in the last five rounds.
The way your brain manipulates your vision 24/7, with no way to get around that, is truly crazy to me. There's all sorts of effects in your visual system like edge detection and certain types of stimulus suppression that it's crazy we even feel like reality is coherent.
Readit News
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.
(Source: doing object photography.)
My studio gets very little natural light, so selecting optimum light sources is crucial. At one time the most practical option was D50 compliant fluorescent tubes, but these were only fairly acceptable.
Situation with LED lamps is also difficult. Even CRI 90 is inadequate, mainly poor red emission and excessive blue radiation. However D50 compliant LED fixtures are available if somewhat more expensive vs. typical LED lamps.
One vendor worth checking out is Waveform Lighting [0]. They offer several types of products with CRI 95 and CRI 99. I've been using their D50 'shop light' for several months and find it very satisfactory.
[0] https://www.waveformlighting.com
I suppose if you want to get closer to sunlight, you need a carbon arc, which is only a few hundred degrees cooler and again, a perfect black body emitter.
> Swear on me mum I saw a game about kerning and alignment years ago on HN
Can't Unsee - https://news.ycombinator.com/item?id=27188989 - May 2021 (126 comments)
“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
One should only take such tests seriously if one's using a properly calibrated monitor and it's viewed under ideal viewing conditions.
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?
Let's say the device has a "24 bit color display". What about eye protection color shifting? This limits the color space used could reduce the effective remaining bit depth. Or maybe they do temporal dithering to get more bit depth? Or maybe the 24 bits are already achieved with temporal dithering?
It does not need to be a calibrated display, but a cheap tablet in sunlight will be worse than a color grading monitor in a reference environment.
I hope they also register the devices used and analyze the statistics on that.
I would only expect poor calibration to break this test for colors near the edge of the display's gamut, or if there's a drastic-enough shift that the color space's lack of perceptual uniformity means a numerical difference that should have been visible ends up in a different part of the color space where that same numerical difference is not perceptible.
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.
Another related effect is flickering of badly designed lighting only in my peripheral vision. When looking directly at the lights they look fine, but when the lights are in my peripheral vision they appear to flash distractingly. I think the peripheral vision is optimised to detect fast changes/movements. At least, that makes sense based on evolution.
https://en.m.wikipedia.org/wiki/Averted_vision
I've also had eye floaters which cause things to distort and can be hard to see through. For about 6 months I had a large one in the center of my left eye vision, which was a bit scary when I discovered I might not see a car reflected in my wing mirror.
I've had it happen many times and it's usually followed by a regular headache. Quite terrifying the first few times it happened to me. Felt like I was losing my sight.
Spending the whole night gaming when I was younger would sometimes trigger it in the morning. Thanks to not having any more time for that, it hasn't happened in years.
Got 14/20
The way your brain manipulates your vision 24/7, with no way to get around that, is truly crazy to me. There's all sorts of effects in your visual system like edge detection and certain types of stimulus suppression that it's crazy we even feel like reality is coherent.