Watercolor paintings are often called “luminous,” but what does that mean and how can you get more luminosity in your paintings?
“Luminous” is one of those confusing watercolor terms that seems like it should have an unambiguous technical definition, but it actually has many possible meanings.
“Luminous” literally means “emitting light.” Of course, that’s something paint on paper can’t actually do. In painting, “luminous” is a description of the feeling that some images can create, that makes it seem as though they are bursting with light.
Bruce MacEvoy writes,
“Luminosity” is a kind of color illusion, an effect of all the colors in a painting working in context to create effective contrast or the representation of light and space. It is the visual quality of an image, not of the paint or paper.
Bruce MacEvoy, handprint.com: secret of glowing color
There are many ways to create this illusion in watercolor. Below, I’ll describe the various ideas that people may be discussing when they discuss “luminosity,” and how to boost each one in your paintings. This turned out to be kind of a roundup of various ideas I’ve been kicking around and solidifying!
Possible definitions of luminous (and how to boost them)
Transparent
Transparency is the characteristic that gives watercolor its unique look compared to other forms of painting. In watercolor paint, pigments are suspended in a transparent binder, and the thinning medium is clear water. In most cases, you can see the white of the paper through the paint. This makes colors look lighter and brighter.
Transparent layers of paint can also be laid on top of each other, making watercolor perfect for painting semi-transparent materials through which light shine, such as a diaphanous fabric or a leaf in the sunlight.
Transparency is the reason why watercolor, as a medium, is often called luminous. That said, it’s certainly possible to create the appearance of light in other media, such as by using semi-transparent glazes in oils, or by using one of the tips below that don’t rely on transparency.
To boost transparency…
Add more water
Mixtures that are highly diluted are more transparent (since water is clear), and mixtures that are mostly pigment will tend to be more opaque.
Choose transparent pigments
Specific watercolor pigments differ in how transparent they are. This information is usually included on the packaging or the catalogue, with paints being rated from transparent, to semi-transparent, to semi-opaque (sometimes), to opaque.
All watercolor paints are transparent when diluted with enough water, but some remain transparent or semi-transparent even when the mixture is thick and mostly paint. (In his post secret of glowing color, Bruce MacEvoy also explains that this is mostly because transparent pigments have a higher tinting strength, so less pigment is needed to achieve a strong color. The pigments that are more opaque are weaker, so paint manufacturers put more pigment in the mix, and you can see less of the paper in between.)
Some of the most transparent are the phthalo blues/greens, quinacridone reds/pinks, and heavy metal complex yellows like Nickel Azo Yellow. Pigments considered opaque include the cadmiums, the cobalts, Titanium White, and some earths such as Yellow Ochre and Indian Red.
High Chroma
Sometimes when people refer to luminosity, they are actually referring to the chroma of the color. Chroma is one of the three aspects of color. Chroma may also be referred to as brightness, saturation, or vibrancy. The opposite is dullness or mutedness.
To boost chroma…
Choose high-chroma paints
Choose bright colors to paint with! Easy enough.
The brightest colors you can get are those with fluorescent additives, such as Opera Pink, but be aware these are fugitive (not lightfast, will fade over time when exposed to light).
Limit mixing (or only mix color wheel neighbors)
You can’t mix a brighter color. Any time you mix together colors, the mix has a lower chroma than the component parts, due to subtractive color mixing (see The Science of Color). The brightest color you can get from a paint is the unmixed shade, fresh from the tube or pan.
To preserve the chroma of your mixes, try to mix together colors that are close together on the color wheel. This limits the amount of chroma you lose in the mix. By contrast, if you mix together colors that are opposites on the color wheel (such as pink and green, yellow and violet, or blue and orange), you will get close to a neutral gray.
Create contrast with low-chroma surroundings
Sadly, adding more and more bright colors will not necessarily make your overall painting look higher-chroma or more luminous. The colors may compete with each other. You’ll be forever chasing brighter and brighter colors unless you get off the hamster wheel and embrace contrast.
Contrast is the most powerful way to make your colors look bright in context, without buying new paints. Paint a swatch of a color out with no context, and it may look “meh.” Paint this same color in a scene surrounded by much grayer, lower-chroma, more neutral colors, and now it pops! Jeanne Dobie calls this effect mouse power, meaning the mousy grays have the humble power to make other colors seem stand out, “like a jewel in a setting.”
Warm Color Temperature
When the viewer says that a scene looks light-filled, they may be responding to colors with a warm color temperature, such as yellow, orange, and red. Certain cool, bluish light exists, but many people associate yellower temperatures with the color of the sun, especially early and late in the day.
To boost warm temperatures…
Use more yellow.
Simply use more colors with a warm color temperature, such as those in the yellow to orange family.
Start with a yellow underpainting.
Some artists start nearly every painting with a yellow underpainting (a layer of light yellow paint that is allowed to dry before continuing). Then, the color that “shines through” the transparency of the other colors is yellow-toned rather than pure white. This can give everything a sort of warm glow. If you are using this technique, don’t forget to preserve any pure whites or other areas that you don’t want to be underpainted yellow.
Create contrast with cool colors.
Again, contrast is our friend. To highlight or feature warm yellowy colors (make them look more yellow), put them next to the opposite on the color wheel – blue-violet.
Light Value
Value means light vs. dark. Another way make a painting look light-filled is to feature light values, or colors closer to white. Scenes with mostly light values may be called “high key,” as opposed to scenes with mostly dark values which are called “low key.”
To boost light values…
Preserve whites.
The most common way to include the color white in a watercolor painting is to leave the white of the paper – that is, leave the white part unpainted. There are various ways to preserve whites, including negative painting (painting around the white object) or using masking fluid. “Losing your whites” – forgetting to leave some areas unpainted, or unintentionally getting paint on them – is a common way that watercolor paintings become unexpectedly dark.
Add water (increase transparency).
Diluting your paints with lots of water makes them lighter in value as well as more transparent.
Create contrast with dark values.
As with chroma, you can heighten the effect of value through contrast: make your lights look lighter by also including very dark darks in the scene. A high key scene may be more light than dark, but it should contain some dark in order to have something to compare against. If everything is light, the whole scene may just look washed out and incomplete.
Create a glowing effect by placing midtones next to lights.
Using value contrast can be a little more complex than simply laying in lights next to darks. If you are trying to suggest that an element in your painting emits or reflects light, you’ll get more white glow if you place half-tones immediately next to your lightest lights. The darkest darks need to go a little further away in this case.
Just a vibe
One of the tricky things about the term “luminous” is that it may not have a specific technical definition at all; it may be a general feeling. Some paintings convey a strong sense of light even though they use relatively low chroma colors, opaque paints, or are overall low-key. It comes down to the way the various properties of paint are combined, the overall effect that is created, and the skill and observation power of the artist.
To boost the vibe…
Observe light.
Light is like any other subject: if you want to paint it convincingly, observe it closely. Your scene will look luminous if it conveys something that feels true and real about light. That generally means being specific: what time of day does your scene occur in? What season? What location? What direction is the light coming from? What is the light source? The more consistent you can make all your cues, the more real the scene will feel.
Use contrast and context.
This has come up in nearly every other category but I can’t stress it enough. Contrast is the secret superpower of visual art. Viewers don’t judge each element of your painting in isolation, they look at a whole scene at once. The way they interpret each element depends on context: what’s around it? In general, to make something look more [fill in a quality here – light, dark, bright, muted, reddish, yellowish], put it next to its opposite.
Beginners (including myself) often tend to overestimate the importance of the paint qualities and underestimate the importance of context. While paints themselves are often described as being luminous (or not) based on their transparency and chroma, really they can’t be judged in a vacuum. Even colors that are muted and opaque may be used to create a luminous effect in the right context.
Conclusion
“Luminous” can mean a lot of things. Because of the vagueness and subjectivity of the term, it can be confusing, and different people may mean different things by it. It can be difficult to create a luminous effect in a painting, but the good news is that there are many possible paths to get there.