A palette may hold a modest number of paints and still produce a wide range of mixtures. The difficulty is that the colours do not behave alike. Some remain clear when diluted, some settle into a grainy surface, and some mixtures lose their brightness sooner than expected.
A watercolour pigment mixing chart gives these differences a place to be seen. It is not a test of colour theory or a display piece. It is a working record: a quiet sheet of paper that shows what two paints do when brought together in different proportions.
The method below uses a two-colour grid. You can make one for a pair of paints, a whole palette, or a small group of colours you often use together.
Materials and preparation
You will need:
- Watercolour paints
- Watercolour paper
- A round brush
- A palette or mixing surface
- Clean water
- Pencil
- Ruler
- Paper towel
Use the same paper you normally paint on, or a similar sheet from the same pad. Paper affects the spread, drying, and appearance of a wash, so a chart made on smooth printer paper may not tell you much about your painting paper.
Choose two paints for the first grid. It is useful to begin with colours that you regularly place beside one another, rather than selecting only the most unusual paints. A warm red and a blue, a yellow and a green, or two earth colours can each reveal different kinds of behaviour.
If the paint names or pigment information are printed on the tube or pan, keep the labels nearby. Record them as accurately as you can. A colour name alone may not tell you whether a paint contains one pigment or several.
Let the paper rest flat before drawing. If it curls easily, secure the corners with low-tack tape or place a clean weight near the edges, away from wet paint.
Photo by Eleonora Catalano on Unsplash.
Draw the mixing grid
1. Mark the paper
With a pencil and ruler, draw a square grid with the same number of columns and rows. Five by five is a comfortable starting size. It is large enough to show a progression without making the sheet unwieldy.
Leave a little room around the grid for labels. Write the name of one paint above the columns and the name of the other beside the rows. If you know the pigment names, include those as well.
The upper-left corner will represent the mixture of the two paints together. The top-right corner can be reserved for the first paint at full strength, and the bottom-left corner for the second paint at full strength. The remaining cells will show intermediate mixtures.
The exact orientation does not matter. Consistency does. Once you have made several charts, using the same direction for every sheet will make them easier to compare.
2. Prepare two clean wells
Place a small amount of each paint on the palette. Work with a clean brush and enough water to make the paint move, but not so much that every mixture becomes a very pale stain.
Rinse the brush thoroughly between colours. Blot it lightly on the paper towel so it remains damp rather than dripping. Dirty water and a brush loaded with yesterday’s colour can change the result before the first square has dried.
For a useful chart, aim for a similar wetness in each mixture. Perfect uniformity is not necessary, but a watery wash beside a thick, nearly undiluted stroke makes comparison difficult.
3. Paint the single-colour edges
Begin with the two outer edges that show each paint alone. Fill the top row or column with the first colour, changing gradually from a strong mixture to a more diluted wash. Do the same with the second colour along the other edge.
Paint each square in a single, even pass where possible. Avoid repeatedly scrubbing the paper. Watercolour paper can be disturbed by too much brushing, and a roughened surface may make a colour appear cloudier than it would in normal use.
Leave a small gap between squares if you want the pencil lines to remain visible. Alternatively, touch the edges neatly and allow each section to dry before working beside it. The chart is a record, not a race.
4. Mix the interior colours
The centre of the grid contains the mixtures. For the first interior square, take a small amount of the first paint and add a small amount of the second. Move across the row by increasing the proportion of one colour while reducing the other.
A simple five-part arrangement might be:
- Mostly the first paint
- The first paint with a little of the second
- An approximately even mixture
- Mostly the second paint with a little of the first
- Mostly the second paint
Repeat this progression on each row or column. Work with freshly mixed paint rather than dragging colour directly from a neighbouring square. That keeps the proportions more deliberate and prevents one cell from contaminating the next.
You do not need to measure drops or weigh pigment. The purpose is to create visible steps between the two paints. If two adjoining squares look almost identical, make a stronger difference in the next chart.
5. Let the chart dry fully
Watercolour often changes as it dries. A wet mixture may look darker, more saturated, or more unified than it will appear later. Set the sheet aside until all of the squares are dry before making judgements.
Keep the chart flat while it dries. Do not stack damp pages. If a pool has formed in one square, you can touch the edge of a clean, slightly damp brush or paper towel to the pool and lift a little water, but avoid disturbing the pigment unnecessarily.
Photo by Sarah Brown on Unsplash.
Record what the colours are doing
Once dry, add notes in the margin. The most useful observations are usually practical rather than poetic.
Record whether each paint appears transparent, semi-transparent, or more covering on your paper. A transparent colour may allow the paper to remain bright beneath a thin wash, while a more opaque colour may look denser. This is best treated as an observation of your particular paint and paper rather than a permanent rule.
Note granulation as well. Some pigments settle into the texture of the paper, giving a mottled or grainy appearance. A mixture may granulate more strongly than either colour alone, or the effect may become difficult to see when one paint dominates. Write down what is visible after drying.
Other useful notes include:
- Which mixtures remain clear and lively
- Which mixtures become grey, brown, or dull
- Which pair creates a useful dark
- Which colour overwhelms the other quickly
- Which mixtures separate into distinct particles
- Which combinations are pleasant for soft washes or distant passages
If the paint is a commercial mixture containing more than one pigment, mark that beside its name if the information is available. A chart records the behaviour of the paint in your hand; it does not necessarily isolate the behaviour of a single pigment.
Use a pencil for notes so that the written information does not compete with the painted squares. You can also add the date, paper type, and any change in the palette formula. These details become valuable if you replace a paint or move from one paper to another.
Make the chart useful at the easel
Keep the finished chart where you can reach it while painting. A sheet stored in a folder may be carefully made but rarely consulted. If the paper is unmounted, punch a hole in one corner or keep several charts together on a ring. Do not cover the painted surface with adhesive.
When planning a painting, look first for the kind of mixture you need rather than a named colour. A clear middle green, a quiet violet, or a deep neutral may be easier to find by studying the grid than by guessing from the pans.
You can also use the chart to decide which paints deserve a place on a smaller travel palette. A pair that produces several useful mixtures may be more practical than two colours that are individually attractive but difficult to combine.
For a larger palette, make separate charts rather than forcing every colour into one enormous sheet. Small two-colour studies remain easier to read. You might make one chart for the paints used in landscapes, another for figure studies, and another for a limited set of earth colours.
Photo by Sixteen Miles Out on Unsplash.
Mistakes worth avoiding
Using too much water
Very dilute squares can hide the character of a mixture. Use enough water for an even wash, but include some stronger passages so you can see the depth and colour bias of each combination.
Relying on a dirty brush
A trace of a previous colour can make a clean paint appear more subdued. Rinse between mixtures and refresh the water when it becomes visibly cloudy.
Comparing wet paint only
The dry result is the useful result. Wait before deciding that a mixture is too dark, too pale, or too dull.
Making every square identical in size and strength
A chart should be orderly, but it does not need to look machine-made. Clear differences between mixtures matter more than perfectly equal brush marks.
Forgetting the paper and light
Colour changes with the paper beneath it and with the light in which you view it. Store the chart away from strong sunlight, and compare it under the kind of light you normally use for painting.
A continuing record
A watercolour pigment mixing chart becomes more valuable as it grows alongside your practice. Add a new sheet when you introduce a paint, change paper, or notice a mixture that behaves differently from memory.
The finished grids will not remove all uncertainty, and they should not. Watercolour depends on water, drying, surface, and touch. The chart simply gives those variables a visible history. With it beside the palette, mixing becomes less of a guess and more of a familiar conversation between a few well-observed colours.