View Full Version : getting the cleanest undertones

08-17-2002, 01:14 AM
I was wondering; how do you get the undertone of a color in the highest chroma possible?

-tint with white?

I had a feeling that dilution with water would give the highest chroma undertone. So I tried these 3 options on 5 colors, in acrylic, on sketch paper:


For each color, the left is scrubbed to get the undertone, the middle is diluted with water, and the right is mixed with titanium white.

-For the burnt sienna and cad. red. med. hue (both pretty much opaque colors), scrubbing seemed to give the cleanest undertone.

-For the quin. magenta and phthalo green, dilution or tint with white gave the cleanest undertone (about equally)

-For the ultra. blue, it's hard to tell.

Does the difference depend on the color's opacity? I was expecting to get a definitive answer that applies to all colors; i.e. 'dilution with water will always give the cleanest undertone', or something like that.

Drew Davis
08-18-2002, 11:54 AM
As you've found, I don't think the answer is necessarily that easy.

For the dilution and scrubbing, the color of the ground will affect your undertone somewhat. Even "white" papers come in different colors of white.

There's also a good bit of difference in effect between the highly-textured scrubbed versions and the diluted ones. The scrubbed have lots of little high-intensity particles scattered around in the while, forming a lighter tone by optical mixing. (<Waves to Seurat's ghost>) The diluted color is a much more even layer of about the same net color. The tint-with-white could go either way, depending on how you mix the color (in place with a few strokes, as it looks in this photo, or thoroughly on the palette before the color hits the paper). All depends on what effect you want; sometimes it's not just about the color itself.

08-19-2002, 01:21 AM
is this the drew as in drew from a long time ago when i first registered with WC, and you were already a member, so like, that makes you an original?.....that drew?

geez,,,welcome back, and where have you been :)

Drew Davis
08-19-2002, 01:35 AM
Yep, it's me again. (Let me guess, it's the pedantic posts in the Color Theory forum that give me away :)) The "Registered:" date is no misprint. I'm flattered you'd remember.

Where have I been? Just lurking, mostly. WetCanvas started to really take off, and there were lots of pros around with lots of good advice, so I didn't feel a need to keep the joint jumping.

And there's usually this little imp on my shoulder that keeps pointing out that I should talk less and paint more...

08-19-2002, 01:52 AM
Drew, thanks for your input. I must mention that the picture looks a little different than the actual swatches. For example the tints with white of the red and magenta is more intense than shows here.

The tint with white, I just got by mixing with white on the paper. If I had pre-mixed and then painted it on, it would surely been higher chroma.

I'm glad you mentioned that scrubbing gives lots of dark spots where the pigment is concentrated, so visual mixing starts to take place. I tried to scub as smoothly as possible (not easy with acrylics).

Since transparent colors, highly concentrated (as they are in those little spots) are blacker and less chroma, that would explain why scrubbing looks so dull with the transparent colors (magenta and phthalo green).

08-19-2002, 01:54 AM
you're a veritable fountain of information, and WC really needs that.............in fact, i recall saying this very thing in a reply to you.....{M}