I’m going to warn you now, this post is nerdy and I really don’t know yet if it is interesting or valuable… Or just mildly interesting at best.  I find it fascinating, but we’ll see…

I had a great opportunity to have Greg Mortenson stay with me last week and teach a portrait painting workshop in my studio. I learned a ton from him. My favorite part of his stay was staying up late and geeking out over really technical art stuff. We chatted for hours about color and how different artists implemented palettes. Dry stuff, but it was really fun. Greg taught me more about Munsell’s color system. I had some familiarity but he showed me how it can aid in analyzing color. Something that we discovered while chatting and searching the web is that chroma is NOT the same as saturation. It is calculated differently. Different equation. If you want to read more on it, here is a link… and here.

It’s not that important EXCEPT if you think they are the same and are having a discussion with someone about whether chroma increases in the shadows of flesh or stays the same (this happened). Because chroma decreases with value while saturation can stay at 100 percent as a color darkens and decrease as you add white. A small, but important distinction.

Greg and I were talking about chroma and whether it stayed the same or changed as you move from light to shadow. I thought it would be interesting to create some flesh colored spheres and implement a few approaches. I used colors from the 7.5 YR range on the Munsell chart. It comprises a basic range of flesh colors regardless of most ethnicities. 

I made some circles using 8 value steps with the outermost being one value lighter than the core shadow as if there was some reflected light. Then I blurred the circle to make it look smooth. These diagrams don’t shift in hue like real skin does. I kept the hue consistent to reduce the variables and see what happened.

I made examples that reflect various ways I have seen skin painted.

1 keeps the chroma exactly the same. It makes the skin look like plastic.

2 drops the chroma of the shadow. I don’t love this but I see it done.

3 drops the chroma of the highlight and this helps but the skin still looks artificial.

4 starts to get interesting. The highlight and band before the core shadow are greyed down, the chroma going from a 4 to a 2. That subtle change is nice to my eye.

5 keeps the highlight at chroma 4 but drops the chroma of the two bands before the core shadow. This is nice too

6 is the same as 5 but with a larger grey area

7 is closest to Rembrandt and Rubens in how they adjusted chroma as the form turns.

8 is similar to 7 with a larger grey area

9 and 10 are interesting. The light side chroma is dropped whole the shadows stay more chromatic. 9 keeps the band before the core more chromatic though. This is similar to Bougueureau’s flesh, but more Stark and not accounting for hue shifts.

What number do you find appealing for flesh? Do you see one that stands out as best or similar to your approach?

Here are some high quality scans. See if you can see changes in chromatic intensity as the form turns.

For this last image by Bougueureau, I made some of the color spheres based on portions of the painting.

The top sample shows the form of the highlight on the ball of the nose to the nostrils

The middle one is the chest moving from the right side in the light to the shadow under the jaw

The bottom is the cheek in the shadow side.

It is interesting to see the shifts in hue and chroma. It’s not drastic but Bougueureau increased the chroma as he moved from light into shadow.

What is also interesting to consider is that while flesh is observable and quantifiable, artists can make personal aesthetic choices to distinguish their approach. From Guido Reni to Pompeo Batoni to Brom to Frazetta, artists have been making small and subtle changes to the narrow range of chroma and hues of flesh to create very diverse results.

Thanks for reading my post. I hope it was interesting today!

Howard