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    The article doesn’t mention “linear” light (AKA RGB without gamma curve compression). That’s a whole another aspect of color spaces that deserves a blog post on its own.

    In short: color spaces like sRGB, HSL, and CIELAB model approximately how humans perceive color and brightness, but human perception is pretty quirky compared to how light behaves physically. This is especially evident when mixing colors: blending of green and red colors in sRGB makes a brown-ish color that is darker than it would have been in reality.

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      I remember some epic battles at Apple when we were trying to convince the colour science people to look at reported rendering problems with the QuickTime pipeline. They were utterly impenetrable, and would often deflect any concern with, “well, if they would just colour correct their displays …” and like, people, what? We were shipping H.264 to Windows machines and iPods.

      ETA: not that pros using Windows wouldn’t correct their displays, but the number of pros using calibrated displays downloading 1.5Mb/s H.264 from the iTunes Store was vanishingly small.

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        Is the issue here that QuickTime was rendering everything correctly, such that it would look perfect on a color corrected screen, but it looked weird on screens with colors which were completely off? If so, what are you even supposed to do in that situation?

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          The issue, really, was that they wouldn’t even answer the phone unless we could prove that we were viewing the bitstreams on a calibrated monitor – which basically nobody was using. So we’d get the report of some colour problem, and every single time we’d have to go through the same damn dance of “No, it’s not calibrated. Yes, it would be better if it were calibrated. No, it’s not. Yes, it’s on an iPod.”

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        Thanks for this. Understanding colour spaces is pretty important to my work but no one seemed to be able to provide me with a concise explanation of how they work. I got most of it already from wikipedia articles but if I had found this article from the start I would have saved a lot of time, Even with wikipedia I didn’t really get what the whitepoint was in CIELAB until now.