This is awesome—I had never read about this experiment. I'm using the CMF quite heavily right now as I develop a spectral color management system. It's amazing that Maxwell was able to essentially plot out the CMF so early!
That’s really cool — it makes me happy to hear from someone that appreciates the novelty and feat of his experiment just through perceptual matching! The precision he achieved with such limited tools is honestly mind-blowing.
What are you developing a spectral CMS for? Is it for lighting or materials or something imaging related?
The CMS I'm building is for creative imaging—I want to model some specific subtractive processes from the physical world digitally. In the process, I had to come up with a way to convert RGB to spectral power, and was surprised to find that while there's a Spectral -> XYZ function (CMF), there's no industry standard inverse (XYZ -> Spectral). So I came up with a function which allows you to specify three RGB peaks, along with their widths, and it solves for the correct peak levels to reproduce an XYZ equivalent to the input color. This is my idea of fun! haha
Absolutely — these old papers are fascinating. I was also surprised by how much insight is packed into them, especially considering how non-trivial some of it is to unpack. My professor and I spent quite a bit of time reconstructing how the experiment worked from the limited figures.
Maxwell's "color wheel" experiment (https://cudl.lib.cam.ac.uk/view/PH-CAVENDISH-P-02000/1) is more commonly known, which preceded this experiment I wrote about. (Which by the way is also a very clever experiment which blends color by spinning a wheel with different ratios of primary colors).
This is awesome—I had never read about this experiment. I'm using the CMF quite heavily right now as I develop a spectral color management system. It's amazing that Maxwell was able to essentially plot out the CMF so early!
That’s really cool — it makes me happy to hear from someone that appreciates the novelty and feat of his experiment just through perceptual matching! The precision he achieved with such limited tools is honestly mind-blowing.
What are you developing a spectral CMS for? Is it for lighting or materials or something imaging related?
It really is mind-blowing!
The CMS I'm building is for creative imaging—I want to model some specific subtractive processes from the physical world digitally. In the process, I had to come up with a way to convert RGB to spectral power, and was surprised to find that while there's a Spectral -> XYZ function (CMF), there's no industry standard inverse (XYZ -> Spectral). So I came up with a function which allows you to specify three RGB peaks, along with their widths, and it solves for the correct peak levels to reproduce an XYZ equivalent to the input color. This is my idea of fun! haha
Nice work! I really enjoy learning how people did these experiments and learned such fundamental stuff with only "stone knives and bear skins"!
Absolutely — these old papers are fascinating. I was also surprised by how much insight is packed into them, especially considering how non-trivial some of it is to unpack. My professor and I spent quite a bit of time reconstructing how the experiment worked from the limited figures.
Very nice article. I don’t think I was aware of these experiments, but maybe I’ve forgotten?
Apologies if I just missed this, but is there a link to Maxwell’s original findings?
Thank you!
Maxwell's "color wheel" experiment (https://cudl.lib.cam.ac.uk/view/PH-CAVENDISH-P-02000/1) is more commonly known, which preceded this experiment I wrote about. (Which by the way is also a very clever experiment which blends color by spinning a wheel with different ratios of primary colors).
Here's a link to Maxwell's original paper: https://royalsocietypublishing.org/doi/10.1098/rstl.1860.000...
You can see some diagrams of his original apparatus that I worked off of in the last two pages!
https://i.imgur.com/EWqdwMV.png
Awesome read. Thanks for sharing.
Thank you for the encouraging words! I’m glad you enjoyed it.