6 ms·

I didn't learn much from reading this article. Questions linger in my mind, for example: What are the CIE XYZ coordinates of each colored square? What is the sp

by nayuki 11d ago

I didn't learn much from reading this article. Questions linger in my mind, for example: What are the CIE XYZ coordinates of each colored square? What is the spectral distribution of each square? How were the colors chosen?

eviks 11d ago
These aren't appropriate questions for the birthday party
jey 11d ago
You sound like you actually want to just generate them yourself using ArgyllCMS `targen` and `printtarg`.
- rustcleaner 11d ago
  I don't know about him but yes yes I do and you should want to, too! :^)
  - deleted 11d ago
    [deleted]
willtemperley 11d ago
The Wikipedia article is far more informative, though I'm uncertain if read the full dpreview article due to ad-induced nausea. https://en.wikipedia.org/wiki/ColorChecker https://en.wikipedia.org/wiki/ColorChecker
- rwmj 10d ago
  https://en.wikipedia.org/wiki/Color_chart https://en.wikipedia.org/wiki/Color_chart is even better if you want to just know about the subject. The Viking Mars Lander had an early colour chart (three times over, for some reason) as shown in this NASA photo: https://www.msss.com/mars/pictures/viking_lander/22a158corr.jpg https://www.msss.com/mars/pictures/viking_lander/22a158corr....
  - isomorphic 9d ago
    That lander had all sorts of fiddly protrusions on it, so the multiple charts could have been to avoid self-shadowing all of them. Or they were worried about chart stability after shipping it across interplanetary space. Or the test targets were for angles for multiple cameras?
- DavideNL 10d ago
  > "read the full dpreview article due to ad-induced nausea" lol, made me chuckle. Tip: 1. install "uBlock Origin", and configure it to "Medium Mode" [1] 2. Install "Obsidian Web Clipper" and use the "Reading View" button to read articles [2] Trust me, you'll love it. [1] https://github.com/gorhill/uBlock/wiki/Blocking-mode#medium-mode-details- https://github.com/gorhill/uBlock/wiki/Blocking-mode#medium-... [2] https://addons.mozilla.org/en-US/firefox/addon/web-clipper-obsidian/ https://addons.mozilla.org/en-US/firefox/addon/web-clipper-o...
michaelt 10d ago
> What are the CIE XYZ coordinates of each colored square? In the most expensive versions, they measure each individual patch, in case printing imperfections make the colours slightly different. And of course because you can’t get the exact same inks when a product is 50 years old! > How were the colors chosen? Skin and foliage; primary colours; greyscale; and miscellaneous. They also make a 140 colour patch version - the “ColorChecker Digital SG” - that provides more coverage; 14 different skin tones instead of 2 for example!
- alwa 10d ago
  Not the exact same inks, for sure, but as a slight tangent—having grown up with RGB/YUV/CIE coordinates and Pantone swatches and process-color printing, but without painterly training, I’d long imagined the world of physical color reproduction to be largely continuous over the perceptible gamut. In the spirit of the classic “Reality Has a Surprising Amount of Detail,” [0] I realized relatively late in life how finite and how discrete the set of colored substances—pigments, dyes, inks, reflective nanostructures—is. That, for example, ultramarine means ~the same thing today as it did in the lapis mines centuries ago, and so on. Frustrated, of course, by things like impurities and degradation at the hands of time and light and medium… but nevertheless finite sets of color-reflecting substances and applications at the bottom. In my case, it was the Forbes Pigment Collection that got me started thinking about it: https://harvardartmuseums.org/article/pigment-collection-colors-all-aspects-of-the-museums https://harvardartmuseums.org/article/pigment-collection-col... And the strange notion of “new” colors, like YInMn Blue [1], and formulations, like Klein Blue [2] (to dwell just on ultramarine-style blues!) …I still don’t have a firm enough handle on color in all its glorious complexity to have a real point: you’re right of course that even within tightly-controlled production processes anchored in chemical reality, things drift and it’s worth paying somebody to measure if it’s important to be right—I just thought I’d offer the notion as a Sunday morning treat, in the hope that somebody else found the rabbit hole as delightful as I did :) [0] https://johnsalvatier.org/blog/2017/reality-has-a-surprising-amount-of-detail https://johnsalvatier.org/blog/2017/reality-has-a-surprising... [1] paper (PDF, open access): https://www.sciencedirect.com/science/article/pii/S2590049822001199 https://www.sciencedirect.com/science/article/pii/S259004982... blurb: https://chemistry.oregonstate.edu/chemistry-news-events/yinmn-blue https://chemistry.oregonstate.edu/chemistry-news-events/yinm... [2] https://www.centrepompidou.fr/en/pompidou-plus/magazine/article/the-untold-story-of-the-international-klein-blue-ikb-of-yves-klein https://www.centrepompidou.fr/en/pompidou-plus/magazine/arti...

by nayuki 11d ago

eviks 11d ago

These aren't appropriate questions for the birthday party

jey 11d ago

You sound like you actually want to just generate them yourself using ArgyllCMS `targen` and `printtarg`.

rustcleaner 11d ago
I don't know about him but yes yes I do and you should want to, too! :^)
- deleted 11d ago
  [deleted]

willtemperley 11d ago

The Wikipedia article is far more informative, though I'm uncertain if read the full dpreview article due to ad-induced nausea. https://en.wikipedia.org/wiki/ColorChecker https://en.wikipedia.org/wiki/ColorChecker

rwmj 10d ago
https://en.wikipedia.org/wiki/Color_chart https://en.wikipedia.org/wiki/Color_chart is even better if you want to just know about the subject. The Viking Mars Lander had an early colour chart (three times over, for some reason) as shown in this NASA photo: https://www.msss.com/mars/pictures/viking_lander/22a158corr.jpg https://www.msss.com/mars/pictures/viking_lander/22a158corr....
- isomorphic 9d ago
  That lander had all sorts of fiddly protrusions on it, so the multiple charts could have been to avoid self-shadowing all of them. Or they were worried about chart stability after shipping it across interplanetary space. Or the test targets were for angles for multiple cameras?
DavideNL 10d ago
> "read the full dpreview article due to ad-induced nausea" lol, made me chuckle. Tip: 1. install "uBlock Origin", and configure it to "Medium Mode" [1] 2. Install "Obsidian Web Clipper" and use the "Reading View" button to read articles [2] Trust me, you'll love it. [1] https://github.com/gorhill/uBlock/wiki/Blocking-mode#medium-mode-details- https://github.com/gorhill/uBlock/wiki/Blocking-mode#medium-... [2] https://addons.mozilla.org/en-US/firefox/addon/web-clipper-obsidian/ https://addons.mozilla.org/en-US/firefox/addon/web-clipper-o...

michaelt 10d ago

> What are the CIE XYZ coordinates of each colored square? In the most expensive versions, they measure each individual patch, in case printing imperfections make the colours slightly different. And of course because you can’t get the exact same inks when a product is 50 years old! > How were the colors chosen? Skin and foliage; primary colours; greyscale; and miscellaneous. They also make a 140 colour patch version - the “ColorChecker Digital SG” - that provides more coverage; 14 different skin tones instead of 2 for example!

alwa 10d ago
Not the exact same inks, for sure, but as a slight tangent—having grown up with RGB/YUV/CIE coordinates and Pantone swatches and process-color printing, but without painterly training, I’d long imagined the world of physical color reproduction to be largely continuous over the perceptible gamut. In the spirit of the classic “Reality Has a Surprising Amount of Detail,” [0] I realized relatively late in life how finite and how discrete the set of colored substances—pigments, dyes, inks, reflective nanostructures—is. That, for example, ultramarine means ~the same thing today as it did in the lapis mines centuries ago, and so on. Frustrated, of course, by things like impurities and degradation at the hands of time and light and medium… but nevertheless finite sets of color-reflecting substances and applications at the bottom. In my case, it was the Forbes Pigment Collection that got me started thinking about it: https://harvardartmuseums.org/article/pigment-collection-colors-all-aspects-of-the-museums https://harvardartmuseums.org/article/pigment-collection-col... And the strange notion of “new” colors, like YInMn Blue [1], and formulations, like Klein Blue [2] (to dwell just on ultramarine-style blues!) …I still don’t have a firm enough handle on color in all its glorious complexity to have a real point: you’re right of course that even within tightly-controlled production processes anchored in chemical reality, things drift and it’s worth paying somebody to measure if it’s important to be right—I just thought I’d offer the notion as a Sunday morning treat, in the hope that somebody else found the rabbit hole as delightful as I did :) [0] https://johnsalvatier.org/blog/2017/reality-has-a-surprising-amount-of-detail https://johnsalvatier.org/blog/2017/reality-has-a-surprising... [1] paper (PDF, open access): https://www.sciencedirect.com/science/article/pii/S2590049822001199 https://www.sciencedirect.com/science/article/pii/S259004982... blurb: https://chemistry.oregonstate.edu/chemistry-news-events/yinmn-blue https://chemistry.oregonstate.edu/chemistry-news-events/yinm... [2] https://www.centrepompidou.fr/en/pompidou-plus/magazine/article/the-untold-story-of-the-international-klein-blue-ikb-of-yves-klein https://www.centrepompidou.fr/en/pompidou-plus/magazine/arti...