We talk a lot about color (in art in general and in this blog specifically), but I feel like discussions can get muddied when we’re not specific about which aspect of color we mean. When we say things are different colors, what do we mean? We may be referring to multiple aspects of color:

• Hue: This is what most people think of first when they think of the word “color”: whether a color is red, yellow, blue, purple, etc. The colors we have names for are arbitrary categories, but generally we’re talking about the spectrum of the reflected light. This is often represented by a color wheel.
• Value: Light vs. dark
• Chroma: Bright and vibrant vs. muted and desaturated

What’s the most important aspect of colorful paintings? In this post, I’ll pit these aspects against each other to see who comes out on top!

Adjusting color variables in watercolor painting

If you’ve ever used software with a color picker, you may be familiar with the process of changing these variables individually.

For example, in the above screenshot from Google Docs, you brighten the chroma by moving left-to-right, darken the value by moving up-to-down, or change the hue on a separate slider. 

Each of these variables can be varied individually in paint, too, but it can be a bit trickier to change just one and hold the other two constant in a physical medium. I’ll change the order in which I talk about them from “what you think of first” to “easiest to hardest to change.” 

Changing value

The same paint may be painted at different values. Generally, in watercolor, we vary value by diluting: adding more water makes the paint more transparent, allowing more of the white of the page to show through. The “masstone,” the thickest concentration of paint, is as dark as that particular paint gets. 

In opaque paint media, such as oils/acrylics/gouache, it is more common to lighten the value by adding white paint.

Changing hue

Each paint has a particular hue. To get a different hue, you can switch to a different paint, or mix paints. 

Quinacridone Rose and Phthalo Blue are examples of paints that have similar value and chroma; the primary difference is hue, pink or blue. If you mix the two together, you get violet – a hue that falls in between pink and blue on the color wheel. You can adjust the hue by adding more pink or more blue.

Changing chroma

Chroma, like hue, is a characteristic of a particular paint. Like hue, you can change it either by switching to a different paint or by mixing with a different paint. 

Phthalo Blue and Prussian Blue are examples of paints that have a similar hue but different chroma.

Both are cyan in hue, but Prussian Blue is lower chroma. Even at points along the gradient when they are the same value – such as when both are quite diluted – Prussian Blue remains more muted/less bright than Phthalo Blue. 

If you want to paint a high-chroma color, you generally have to choose a paint that is the right color. An unmixed paint is at its maximum chroma. Mixes are always lower chroma than the component parts. There is no way to mix low-chroma paints and come out with a high-chroma mix.

If you want a low-chroma color, you are in luck. There are myriad ways to create low-chroma mixes from high-chroma paints. Adding nearly anything will lower the chroma at least a little. Your options are more limited if you don’t want to also change the hue. Basically, you are looking for anything that would get you closer to dull gray. This includes:

• Mix in black – this also tends to darken the value, but you can make up for it by diluting the paint.
• Mix in the complement, or opposite on the color wheel. For example, adding orange to blue. This also tends to darken the value and may change the hue, depending on how much is added.
• Mix in multiple other paints so that the total adds up to gray. For example, if you have a primary color, mix in the other two primary colors. Again, this tends to darken the value and may change the hue depending on the balance of the mix.

Phthalo Blue (Green Shade) and Pyrrol Scarlet are mixing complements; as you add more Pyrrol Scarlet, the blue gets grayer, and as you add more blue, the scarlet gets grayer. A fairly balanced mix is black/gray.

So what’s more important?

The question of what’s the most important aspect of color is extremely subjective and has no right answer, which is why I’m definitely going to take it on. 

Contender #1: Hue

This is the aspect of color that colloquially we usually mean when we say “color,” and we have lots of words for different hues. When we describe the colors of things, we use hue words: “on a tree, leaves are green, the trunk is brown.” 

Hue is often the subject of deep love and appreciation: people have “favorite colors” (favorite hues). Mine are pink and teal, for example. Hue can also cause extreme negative reactions, such as nausea or disgust. 

Hue can have a large emotional effect on the scene. A scene dominated by cyan blue may be seen as cheerful or serene. The same scene in warm golden brown hues may be seen as nostalgic. Pink looks dreamy, while purple-blue looks moody.

I have a huge respect and love for hue. Often the desire to recreate or explore a particular hue is what makes me want to paint something in the first place.

The problem is that hue alone can’t do it all. Without sufficient variation in value, paintings look flat and lacking in depth.

Children are usually taught to color in terms of hue alone, so sticking to hue variation alone can appear childlike. This can be an intentional stylistic choice, as in certain illustrations and cartoons, but can also be a point of frustration for beginners who don’t understand why their paintings look flat.

Contender #2: Value

Value alone has incredible power to convey a complex image. Value shows you where the light is shining and where it is shaded, which defines the planes and textures of the object. An image that has a rich range of lights and darks, but no hue information at all, can still look detailed, lifelike, and three-dimensional, such as a black-and-white photograph.

Getting the lights and darks right is what makes an image look three-dimensional. For that reason, art teachers often stress the importance of value. The adage “Value does the work, color gets the credit” is a classic for a reason: it stresses to beginners that they are probably overestimating the power of hue and underestimating the power of value.

Recently a friend told me he’s surprised by how well he’s doing in his beginner painting class because he is colorblind and thought this would be a drawback. On the contrary, his paintings, which tend rely on value rather than color to convey meaning, are often more realistic and compelling than those of his classmates who are faithful to the hues they see but underestimate the variation in value.

My personal problem is that value is, well, it’s not colorful. You don’t need to use black and gray to make a value study – you could use any color as long as it has value range – but whatever you use, it will lack hue variation. Certainly nobody would use the word “colorful” to describe a monochrome painting.

Value definitely wins if our question is “which aspect of color best helps us to define depth in a convincing three-dimensional painting?” But if our question is specifically about what helps us to paint a colorful painting, then value cannot win.

Contender #3: Chroma

Chroma is probably the least-discussed aspect of color. I have found that it is often lumped in with other discussions. Sometimes people round it to the hue (describing high and low chroma versions of the same color wheel segment as different hues). Other times, they mistake it for value (assuming high chroma = light value). Many artists use chroma skillfully, but do not realize they are doing it. For example, they may claim they made part of the painting stand out by using a lighter value or a contrasting hue compared to the background, and not realize or articulate that they also used a higher chroma.

I find it quite difficult to isolate the effects of chroma. How can you create or even imagine an image that only varies in chroma and not hue or value? We’ve all seen flat illustrative images without value variation and grayscale images without hue variation, but chroma is more likely to be changed along with one of the other aspects. 

An easier way to play with chroma is to paint the same image in higher or lower-chroma versions. For example, below is a project for a class I took in 2022. I took a “base image”, something I would normally paint, and made a version that’s extremely low chroma (almost grayscale) and then a version that’s extremely high chroma (all bright colors).

I actually like both the desaturated and highly saturated versions of this painting, but I think they create different effects. The desaturated version is a study in value. The super-saturated version creates a feeling of overwhelm and maximalism, which is certainly a legitimate statement to make. But I want to make it intentionally, probably, and not inadvertently in every painting because I refuse to use colors at anything but their maximum chroma.

A trick about chroma is that it is extremely subject to context. For example, I consider Venetian Red a low-chroma scarlet in isolation, but in a painting with mostly grays and one splash of Venetian Red, the Venetian Red can appear very bright by contrast. 

It’s not intuitive (to me at least), but the paintings that feel the most colorful aren’t usually the ones that use all high-chroma colors. They are the ones that mix high and low chroma colors, using the low-chroma colors to set the context and set off the high-chroma colors. The effect of low-chroma colors to support their higher-chroma neighbors is what Jeanne Dobie refers to as “Mouse Power.”

And the winner is… 

All colors have hue, chroma, and value (even black), so asking which is most important is kind of like asking “what’s the most important aspect of a rectangle, length or width?” You can’t not have one. What I am really asking “which is most important to vary in a painting?”

I have to grudgingly admit that the art teachers aren’t wrong: value variation is doing by far the most structural work and has the most ability to effect dramatic changes in the realism, depth, dimension, sense of “pop”, focal point, etc. It’s also the only variable that can stand on its own: a scene which only varies the value still looks good. In fact, many art forms (such as pencil drawings) only manipulate value and don’t involve other color variables at all. Meanwhile, a scene where everything is the same value tends to be confusing, even if other variables are varied.

I would like to nominate chroma variation as “most underappreciated”, value’s silent partner. When the two are varied together, you get a one-two punch of the appearance of light. Chroma variation is important in making a painting feel colorful, which is an extremely important motivation for me, personally. If you are primarily motivated by a desire to paint dimension or light, value might be enough for you, and the other aspects of color may be an afterthought. But I am extremely motivated to paint color, so while value needs to be in place, I need more.

Hue variation is seems to contribute the least to particular realism effects. You can palette-swap a painting without a strong effect on its legibility. That also means you have the most room to play around and express yourself artisitically, which makes it a strong contender for “most fun.”

In reality, we usually vary all three aspects at once. I found it challenging to isolate one variable at a time for this post; luckily, we don’t normally need to! It’s both easier and more effective to use all the variables together.

Which is most important to vary in a painting? It depends on the effect you want to create. Here are some examples of ways the three variables can work together to create an effect.

To create an effect of…	Main Value	Main Chroma	Main Hue
Light	light	bright	yellow
Shadow	dark	muted	blue
Distance (atmospheric perspective)	light	muted	blue
Moodiness	dark	muted	violet
Focal point	contrast w/ surroundings	bright	contrast w/ surroundings

Keeping in mind the different color variables that we have available to us can help us to more intentionally call attention where we want it and build effects such as light, dimension, and emotion.