Temperature of Colour:
Aspiring painters usually understand which colours are warm and which cool, but have less understanding of why temperature bias is so useful in practice.
Within the hues, individual colours veer towards red (warm) and blue (cool), so, for example, Permanent Rose, is a cool red and Ultramarine Blue a warm blue. Knowing the temperature of a colour enables the artist to mix colours extremely efficiently. The two colours above would mix to make a bright violet because both are already veering in that direction.
Everyone knows blue and yellow make green, but if you mixed Ultramarine Blue with Indian Yellow you would get a very dull green because both are warm colours, veering towards red, and red, being the opposite of green, dulls the mix.
A bright green is reached by mixing a cool yellow, eg Aureolin, with a cool blue, eg Prussian, because each colour already leans towards green.
It is easier to make vibrant watercolours on pristine paper. That sounds obvious, but often I see painters touching the surface of the white paper with their fingers or the palm of their hand, or rubbing out pencil marks broadly and vigorously. Fingers transfer grease onto the paper and erasers scuff the specially prepared surface. Anything that compromises the appearance of watercolour, however minimally, is not in your best interest. Rub off only the pencil line, avoid the paper either side. I have even seen people stacking their palettes and brushes on top of their white paper, Noooo, keep it covered until the moment you start drawing or adding paint, anything else is self-sabotage!
To understand how the transparency of watercolour works on paper it helps to think of the minute particles of pigment like the millions of pixels on a screen. Watercolour pigments, which are bound in gum Arabic, do not dissolve in the water, the micro-particles of pigment are held in suspension and floated across the paper in the solution of gum Arabic and water. When the water evaporates the gum Arabic dries and sets the tiny particles in place. Light shining on the white paper reflects back through the transparent particles, and may be refracted, and bounces back from the white paper spaces left between the opaque particles. Now you can see why it is so important not to block out the light with too many layers of paint or to push the pigment around on the paper into clumps. Keep your pigment happy and it will reward you with the luminosity for which watercolour is famed.
Fear of failure sometimes prevents us from experimenting and taking risks in watercolour. We start a painting with such hope and excitement and too often end with an awful feeling of disappointment when it goes wrong. But is this failure? What have you actually lost? The brushes are still there; the amount of pigment squeezed probably barely indented the tubes; the only thing ‘lost’ is the lovely clean piece of paper (even this can be recycled by over-painting with pastel or priming for oils). Is the time wasted? Usually we learn more from the paintings that go wrong than from the paintings that go right. So if nothing is actually lost why fear ‘failure’. Failure is a necessary part of the creative process.
Here are some of my favourite quotes:
Richard Branson: “To increase your success rate, increase your failure rate”
Pushkin: “We can try, and fail, but we shouldn’t fail to try.”
Tiger Woods: “I am my own worst critic, but I never undermine my own confidence.”
Exodus: "Do not linger, move on"
Knowing the properties of the pigments used to make your watercolours makes it possible to guess which colours are opaque and which transparent. If the micro-particles of coloured pigment are extracted from metals, eg Cadmium Red, Cadmium Yellow, or Cobalt Blue, you can guess that the minute pigment particles would be fairly dense and therefore likely to be somewhat opaque, whereas those extracted from carbon (eg Permanent Rose and Permanent Sap Green or the polysyllable names like Quinachridone Red and Indanthrene Blue), can be rightly guessed to be transparent since carbon is a lightweight organic material. Likewise, in diffusion, the metal particles are heavier and spread out less rapidly than the lighterweight carbon particles.
Good composition is crucial to the success of painting, but if you are painting outside, planning and drawing for too long can delay catching the very light that attracts you to a subject. You can go straight in with pale washes to establish the composition, especially if short on time, or if a drawing is required to position items, make it a guide for the brush, to tell it where it can and cannot go. You can always draw more detail into a watercolour as you go along, don’t waste precious time at the start on detail that may quickly be covered up, especially in the shadows. If you begin from the middle of the paper or with the thing that most interests you, it may not matter if the rest is unfinished when you have to stop.
Many painters get hung up on anxiously trying to match, as closely as possible, the colours in their painting to the colours in their subject. Worry less about the actual colours of your subject and concern yourself instead with the relationships between the colours within your painting. Matisse says it perfectly: “There can be no colour relations between it (your subject) and your picture; there are the relations between the colours in your picture, which are the equivalents, substitutes or representations of the relations between the colours in your model."
Artists often talk about "painting the light" but In watercolour we have to not paint the light to "paint the light"!!! With watercolour the untouched paper represents the lightest lights and white so we have to paint the area around the light or white to bring it into being, ie in order to paint the light a watercolourist must paint the shade!
[Cobalt Blue is a warm semi transparent blue, ideal for the limpid shadows that play over white petals.]