a new step: color with colors
CLICK! on the picture TO ZOOM!
Average colors of the Blackbody radiation colors (from 3500°K to 9500°K) and the color of the background. 50% of the paper is covered by paint. (This actually equals a desaturated picture of these colors, i.e. the mixture of blackbody colors and white D65 light at equal power)
Doing optical greys with colors might become history in my work, I start doing colors with colors – let me say something about my color system here:
I use colors following “Grassmann laws,” that means that I measure the lights coming from my pigments to your eyes, and by varying the proportions of these pigments I change the average color of the light that comes to you.
That works exactly in the same way as you computer’s screen except that I have more primary colors and usually less light.
Here, I used 7 “primaries”: Ultramarine Blue greenish extra, Cobalt Turkish light, a Green mixture of the former and of the next, Cadmium Yellow light, Cadmium Red “Cinnaber” shade and Titanium White (see below)
To create a color, I will make the average of 4 of these primaries, so a “possible” color will always be located in a “pyramidal space” with a primary color at each peak.
If I add the Black primary, the main pyramids will be:
ReGrBlu-White and ReGrBlu-Black. Around them you’ll have ReGrYe-Whi/Bk ; GrBluTu-W/Bk ; ReBluPink-W/Bk
Which makes a total of 8 pyramids that touch each other and define the gamut of my system! (see below)
8 pyramids = gamut of 8 colors
The best solution to get the amounts a, b, c, d of the colors A,B,C,D required to get a given color M is to use matrix calculus:
the colors coordinates are in the CIE 1931 XYZ color space, so we create a square matrix with the color coordinates for each color, multiply by the solution, and equal it with the color we want:
Then we solve this:
with P being the inversion of our matrix:
Thank you very much PA5CAL from this forum to have helped out!
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Today could be a great day for painting: Georges Seurat’s dream-project of a “scientific painting” advanced a little. I’m sure he would be (very) happy to see this. I wish I had the email of the painter’s paradise, I would send this to him and all his friends…