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by Daub 42 days ago
I have a history of research in computational aesthetics with an emphasis on old master paintings. A few notes:

1. You have used the RGB hue wheel not the RYB hue wheel. The later defines the complementary pairs red/green, blue/orange, yellow/purple which are more useful for an artist when evaluating hue. To those who would say that the difference between RTGB and RYB complementaries is subjective, I would point out that the red/green, blue/orange, yellow/purple pairs have been known by artists since before Newton first expressed hue on a wheel.

2. I think it is fair to assume an artist has a consistent color pallet, but I'm not sure that a genre would.

3. User S0und has implied that paintings have changed too much from their point of creation for your work to be valid. For sure it is true that paintings have oxidized, accumulated multiple layers of dust-attracting varnish and been damaged by UV exposure. However, the relative difference between the colors they have used remains almost the same, and this is where the value of your work lays.

4. The key problem of visualizing the color of a painting is its dimensionality. A standard histogram does a super fine job at expressing the lightness value of an image. A radial hue histogram does the same for the hue/saturation. But there is no 2D graphical visualization that does both. Personally, I would go further and visualize separately the hue, saturation and lightness signatures of the artists. For most pre-modern painters, the lightness values closely mirrored their saturation values. Artists like Gericault and most of the Impressionists learned to separate them.

BTW... do you know this website?: https://www.webexhibits.org/pigments/intro/history.html

2 comments

Great points! 1. I'll try to add RYB option for color harmony wheel 2. You are absolutely correct, there are no consistent palettes across genres, but I thought it will be interesting to see multitude of palettes artists use for the same genre 3. User S0und's observation about oxidized or decayed colors is very interesting, but even with muted, brownish colors these artworks still look amazing. 4. Any suggestion how can I add such color visualization across body of work of a given artist or a style?
> Any suggestion how can I add such color visualization across body of work of a given artist or a style?

I think that the best visualization of the colors of a painting is by using the painting itself.

In class I demonstrate lightness by first desaturating the work (or copy pasting the L in Lab). I then do a controlled posterize on the image - basically a stepped curve in Photoshop. I try to isolate the dark, middle and light. These are relative values that can often manifest as lumps in the histogram. Painters tend to be very deliberate in the way they organize them. This page explains what I am getting at:

https://rmit.instructure.com/courses/87565/pages/colour-ligh...

In my experience such posterizing is best done manually but AI might be able to do it.

Hue at saturation are more difficult for the simple reason that they are difficult to disengage from lightness.

Like lightness, saturation is generally organized according to low, middle and high. For most of art history, the saturation of a painting would closely follow its lightness. It was Gericault who separated them. Check out the saturation vs lightness of his Lobster painting for an example of this.

Hue is a beast. Sure, most paintings done before the impressionists are pretty unsaturated. But even Rembrandt would be careful to use a red brown against a green brown. Check out the Rembrandt image on this page to see this in action.

https://rmit.instructure.com/courses/87565/pages/colour-hue-...

I think that a radial histogram is the best way to visualize hue. This would show not only the hues but there relationship to each other on the RYB wheel and also there quantity. There should be a cut-off point for hue that is visible. In our work we established a cut off - all hues with very low saturation were ignored.

Hope this helps.

I love the website about color pigment history - it explains a lot about some of the color choices artists made in different time periods. Thank you for sharing the link.