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Comment by bhauer | Hacker News Reader

Awesome.

I take issue with that claim that ordinary people can only perceive 1 million colors. That may be accurate but it nevertheless irks me. It serves as justification for the unfortunate situation we have today where although technology has existed for years to provide us with deep color, we are stuck with the 16,777,216 colors provided by 24-bit color.

Despite a large palette, there are several cases where 24-bit color depth yields obvious banding. I've ranted about this previously [1] so I'll leave it at that.

[1] http://tiamat.tsotech.com/24-bit-color-sucks

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They are talking about one million hues. Hues are "pure" colors without saturation and lightness.

So humans can see more than 1 million colors.

Edit: maybe this image will make it clear: http://upload.wikimedia.org/wikipedia/commons/thumb/c/cb/HSL...

I can see gradient step on my HP 2335 (1920x1200) IPS display Monitor (with an LG display panel that was similar to what was used in Apple Cinema Displays of the time). Just giving verbosity of the monitor details for reference. Interesting read though and I found it surprising that even 24bit color can have issues like this. Possible that some high res IPS displays since mine have eliminated the issue (since the 2335 is 4-5 years old now). Wish my 2475 wasn't dead or I would test against that as well. I don't really consider either of these a good comparison, but I don't see it on my Nexus 7 or my Galaxy Nexus (though that's a Pentile AMOLED screen).

Some that cannot see it might have missed the author's advice at the bottom:

I received some great feedback from readers. Most importantly, it was pointed out that some low-cost LCD monitors down-sample to an even worse color depth such as 18-bit or lower. In fact, some readers were not able to see the difference in the colors above precisely because their monitor removed the difference by down-sampling.

The problem with some AMOLED screens is that the different colours efficiency decays at different rates. Which is why early versions of the galaxy(or similar samsung phone) always has that horrid blue-green tint to it.

Another problem is ambient light. if you're wearing a red tshirt, and there is a source of light other than your monitor its going to throw out the colour balance.

There's actually methods being worked on to compensate for color degradation in AMOLED over time[1]. Many of the AMOLEDs being used by Samsung are also Pentile (since they're cheaper to produce), which is even more likely to suffer from what you mentioned as well. Originally, phones like the Galaxy S and S2 did not have a Pentile screen, but starting with the Galaxy Nexus, I think they all have since (including the S3 and the S4, albeit higher quality ones).

[1] http://www.hindawi.com/journals/ijp/2013/839301/

With four cones, she may well be able to perceive electromagnetic waves outside the range we can. In other words, it may not be only about seeing finer colors, it may be about seeing more colors as well.

That should be easily testable..and wouldn't that mean that the colourblind men can do it too, since they have the same non-ideal cones?

Seems to me the banding might be caused by bad rendering, and not a deficiency of 24-bit colours. On my MBP the gradient is indiscernable.

My android 4.1 tablet can't show the gradient...

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