The colors were all based on a set of idealized Primaries.
All of these colors were made from the 3 primaries. There were synthesized in adobe Illustrator to match an Idealized set of R,B and Y primaries. The Illustrator color space is set to CMYK. CMYK is the same as the subtractive color mixing process as mixing color pigments. It’sot perfect at all but pretty damn close. I use this technique for oils and watermedia.
For contrast I asked ChatGPT how many colors of oil paint does Old Holland sell, ChatGPT answered “Old Holland makes 168 colors in their Classic Oil Colours line”.
There are 252 ‘colors’ represented here. Not really a fair comparison be you get the picture.
The mothod of mixing is as follows;
I find the color in the 2 neutral palettes by mixing the tertiaries. To find the metaphoric primaries of Semi Neutral you ix the 2 adjacent tertiary to the primaryies. Yellow Orange and Yellow Green make the Metaphoric Yellow of there semi Neutral. Red Orange and Red Violet make the Metaphoric Red. Blue Violet and Blue Green make the Metaphoric Semi Blue primary..
The Full Intensity 12 color spectrum palette
The Semi Neutral 12 color Spectrum Palette. Note how these colors are not darker, just more subdued.
The Hue or Neutral 12 color Spectrum Palette Note how thees colors are even more subdued.