Lesson 4 - What Colour is That… (Exactly)?

Colour clearly matters hugely to most visual artists, in fact you could neatly describe most paintings as carefully (or not so carefully) orchestrated patches of colour on canvas or paper, and leave it at that.

When musicians talk about music they have the advantage of a universally recognised code or language where specific notes of specific duration can be clearly made visible on a music score. So musicians can talk and think about music without actually picking up an instrument. 

Visual artists are not blessed with anything quite so neat but nevertheless there is an analogous language that can accurately describe colours and their relationships. This can be learned fairly easily, so colours can be thought about and talked about without actually unpacking the paintbrushes.

I am guessing that by now some readers would like me to just shut-up and get on with some quick suggestions for ‘what colours to buy’ but I assure you, if I did this, you’d be short changed. It would be like being dropped off in a foreign county with no map and no guide, which would make getting around after arrival a tad challenging, so I’m asking for your patience, which will be repaid in full, because once you know and understand how colours work and relate to each other you will be able to make your own well informed choice about which colours you might need and which ones you might like to add to my list(s) or even which colours you’ll put onto your own list.

The language of colour is straight forward enough but is made needlessly complex because the Americans will insist on using their own words when perfectly serviceable English ones exist already.

Imagine, if you can, a black and white photo you are familiar with. It will probably carry some meaning for you and have some emotional significance, but viewed dispassionately it is simply a pattern of light and dark areas on a piece of paper. This lightness and darkness is a change in what artists refer to as ‘tone’ (which Americans refer to as ‘value’). The lightest tone can of course only be the white paper and the darkest, the blackest black that can be made. So it is possible to think of, or even make, a tonal scale with say 10 discreet divisions with zero being white and 10 being the darkest black with 8 graded tones in between.

This notion of tone is extremely important and historically many artists used tone with very little actual colour to orchestrate their painted surfaces. If you flick through any book on Rembrandt or Caravaggio you will see what I mean. The drama of the paintings is generated by setting off the darkest darks against the lightest lights and there is very little ‘colour’ in the pictures at all, especially in Rembrandt’s work, and yet they carry as much ‘meaning’ as is needed and a huge emotional punch.

This idea of tone also applies to colours too. Yellow is fundamentally lighter in tone than say blue or red and however deep and dark a yellow is made it can never be as deep and dark as a dark red or dark blue and still be described as yellow.

The map (or score) that allows us to think and talk analytically about colour is of course the ‘colour wheel’ which most of us may be familiar with from primary school. Sadly, the simple primary school version needs quite a bit of sophisticated adjustment to make it work for us as painters although the basic principles remain in place

The primary colours from primary school were (and luckily still are) red, yellow and blue and they are placed equidistant around the outside of the circle and have a special place of honour precisely because they cannot be mixed from any other colours. It’s that precise quality that makes them ‘primary’.

the primary colours

The primary school lesson continues, that on the rim of the circle lie a range of beautiful bright colours, with a whole range of oranges between red and yellow, a range of greens between yellow and blue and a set of purples which lie between red and blue. The exact nature of the colour will depend on the mixture used. For instance an orange made with more red than yellow will make a rich ruddy orange and one with more yellow will form a yellowy orange, and one somewhere in the middle a basic  ‘unbiased’ orange. However, whatever type of colour is made, all of these colours are referred to as ‘secondary’ colours precisely because they are mixed from two primary colours, or to be more precise they are colours which contain only two of the primaries.   

the secondary colours

The exact placing of a colour on the rim of the colour wheel defines its ‘hue’ (or ‘chroma’) and in theory at least there is a particular place of every hue of the rainbow.

So far, so good, but it is clear that the colours that we have identified, are all clear, clean, bright colours, the sorts of colours that appear on kid’s plastic toys, road signs and packaging; colours that hold our attention and are very bold. So what about all the subtle, complex colours that appear in the natural world and especially in landscapes (a subject close to my heart). For readers in the UK, next time you are driving in the country try comparing the myriad greens of foliage with the green used on road signs and you will see exactly what I mean. There are of course obvious exceptions to the ‘natural/subtle vs. synthetic/bold’ split, you only have to bring to mind brilliantly coloured flowers and butterflies or the amazing dazzling colours of tropical fish (or tropical sunsets) but there is clearly a whole family of colours that appear in nature, in abundance, that are not covered and matched by the colours on the rim of the colour wheel.  

natural colour

This is where things get a little more complex although the basic idea is simple enough. The colours I want to talk about here I will refer to as ‘natural’ colours and they do have a place on the colour wheel it is just that it is not on the rim. These natural colours, the greens of foliage, the greys and browns of granite, slate and earth and the subtle greys of clouds, the green greys and indigos of the sea, the subtle oranges, blacks and tans of skin, fur and feather and all the other beautiful colours of the natural world are technically known as ‘tertiary’ colours and what this means is that they are made by the addition of some of all of the three primary colours.

Clearly the big question that needs answering when mixing these colours is ‘exactly how much of each primary colour do I need to mix a certain natural colour’. 

It is at this point that the geometry of the colour wheel comes in useful though I agree that it seems counterintuitive that the application of geometry should answer questions of colour but believe me it does.

There are two very important ideas which will take a lot of the guess work out of colour mixing and it is worth getting to grips with them both before we venture any further. One is that at the very centre of the wheel there lies neutral grey which has no particular bias towards any particular colour on the rim and the second is that when any two colours are mixed the resulting mixture will lie on the straight line that joints the two original colours. With these two simple principles we can make any colour that we wish to make and with a little luck spend far less time randomly guessing at what is needed in the mix.

It is clear that if we draw a straight line from any colour on the rim through the centre of the circle we will arrive at a second ‘twin’ colour on the far side and this twin colour is known as the complementary colour of the first. So Orange is the complement of blue and blue is the complement of orange (it works both ways). Red and Green are complementary colours and so are Yellow and Purple. In fact every colour on the rim has its unique complement. And when we mix a little of a colour’s complement to it the colour loses some of its brightness, purity and ‘punch’ and this change is known technically as a loss of saturation. The first colour has become less saturated. So a useful way of thinking about tertiary /natural colours is that they are primary or secondary colours (out on the rim) that have had their saturation reduced by the addition of a complement and so have been moved towards the neutral centre of the circle. Tertiary colours lie along the ‘spokes’ of the wheel and the nearer they get to the centre the less saturated they become until they lose all of their ‘parent’ colour and become a neutral grey. By thinking about tertiary colours in this way it becomes possible to think more clearly about how they fit on the colour wheel. Each grey, brown, olive or plum can be thought of as lying on a particular spoke of the wheel at a certain distance from the centre. Burnt Sienna for instance is on a spoke linked to orange and just a little way in from the rim, Burnt Umber on the other hand is almost on the same spoke and much closer to the centre.    

the complementary colours

It is in understanding complementary colours that it becomes possible to make accurate judgements about how to mix a particular colour. Any colour on the rim can be peeled away and drawn towards the central neutral grey by mixing in a little of its complement or near complement. A bright Viridian or Winsor Green that would look out of place in a naturalistic landscape can be modified and muted by moving it in towards the centre of the circle by adding a little of one of the reds on the far side of the circle and other useful natural greens can be made by trying some of the near complements like orangey red or yellowy orange.

muting vibrant greens

It is also clear from the fact that colours mix in ‘straight lines’ that mixing a more or less pure blue with a more or less pure yellow will generate a green that is clearly quite a way from the green on the rim. In other words it will be less saturated than either of its two mixing colours. This is important when considering which colours to buy because although it’s true that blue and yellow make green, you will never get a green as saturated as Viridian (which may or may not matter to you)

mixing colours inside the triangle

So now we are a little better informed let’s consider what colours might be worth buying as a starting set, working on the assumption that we want to use only the three primaries. Unfortunately there is no perfect threesome because the actual tubes of paint have very different qualities and none of them are pure primaries, but having said that there are some perfectly workable ‘triads’ of colours that work together to make a useful set, though each set gives a markedly different family of colours and as I have already explained, the colour mixtures that can be made lie only within the triangle formed by the primaries so clean punchy secondaries will always be missing from any simple triad of primaries.

Certain colours are very delicate in nature with little real power or punch but they can be used very successfully where a delicate feel is appropriate, perhaps in flower painting or a very softly coloured landscape, so a set of transparent watercolours that are well balanced would make a good though very specialised threesome. This gentle palette could be made with Aureolin (yellow) Rose Madder Genuine (red) and Cobalt blue. 

The Gentle Palette

If you were looking for something a little stronger (said the barman) and not happy with such a delicate palette, then you can move up the power scale by choosing a set of more powerful primaries though be warned against just adding one strong primary to the delicate set as it will dominate a lot of the mixtures and make the set lop-sided.

Such an intermediate well-balanced set could be formed from New Gamboge (yellow) French Ultramarine (blue) and Cadmium Red. With this set a whole range of strong tertiary colours can be mixed that would be very useful particularly in landscape painting.

The Intermediate set

If you are the kind of person who wants to paint with really intense colours and have no interest at all in things delicate and subtle and loves intense velvety darks and brilliant vibrant lights then you have to choose a set of primaries that have these qualities already. Such a set could be made from Winsor Lemon, Winsor Red and Winsor Blue but be warned: the downside of these particular colours is that they stain the paper (see my earlier blog on papers) and as such you can’t lift the paint once it’s been laid so mistakes can’t be corrected and it would be easy to end up with a very low key painting.

The Power Palette

At this point I want to introduce an idea that I have not talked about before but it is one that is central to discussions about colour. It is the idea of ‘temperature’. Colours can be said to be ‘warm’ or ‘cool’ and this is a relative term and not an absolute one, so it’s a little tricky to pin down. Basically, warm colours have a leaning towards the orange/red side of the wheel and cool colours are biased towards the green/blue side. So if we consider the blues say then French Ultramarine is a warm blue (because it contains some red) whereas Antwerp, Prussian and Phthalo Blue are all cool blues. This is straight forward enough but when you compare other colours the relationships can change. For instance if we compare French Ultramarine with Purple then the blue is the cooler of the two (because purple has more red in it) but if we compare the same blue with a cool blue like Cerulean then the French Ulra is warm. It takes a little getting used to but it is an idea that is very useful in colour mixing and absolutely necessary to understanding what comes next.           

 One of the major problems we run into in choosing a basic triad to work with is that although in theory we should be able to get by with the 3 primaries there are in real life no tubes of paint that match exactly the requirement of being a pure primary. Some reds are orangey reds (warm reds) and some are (cool) purpley reds and so on.  

So a more pragmatic approach is to admit that a pure triad can’t be found and to choose instead two versions of each primary, one cool and one warm so that we can expand significantly the range of colours that can be generated.

Such a set of twinned primaries could be made from say New Gamboge and Lemon Yellow for the yellows, Antwerp Blue and French Ultramarine for the blues and Winsor Red and Alizarin Crimson for the reds. This set will allow for a very broad range of colours and should certainly be enough to get you started. The Ultramarine and Alizarin will make a close approximation to a pure Purple. The Antwerp and Lemon will make a crisp cool green and the New Gamboge and Winsor will make a really strong orange. So there we have it, the six tubes that in theory can be used to make (almost) any other colour you might want; both fairly pure secondary and all the tertiary colours you could wish for.

The Twinned Primaries

However, having given the advice above it is worth saying that it is not the palette I use myself because over the years I have found some other colours more useful and have developed a very personal palette which suits me for the kind of work I do. For instance, in my landscape painting I hardly ever need a very bright yellow and instead find Raw Sienna and Yellow Ochre more useful and very often I will use earth colours like Burnt Umber, Raw Umber and Burnt Sienna as a basis for my greens and greys.

I find that I have a need for the broadest range of blues, which I employ for my skies and seas and obviously for my greens too. I use French Ultramarine and Antwerp a lot but find Cobalt Blue and Cobalt Turquoise Light necessary for Skies and shallow seas and Cerulean Blue indispensable in the mixing of my grey greens.

I seldom need any very strident reds in my landscapes and find Rose Madder Genuine more useful than Alizarin Crimson when I need a cool red.

When it comes to Life Drawing I use a limited palette of Cadmium Red and Raw Sienna for my basic skin tones, which I then modify with Cobalt Blue, Cerulean Blue and Rose Madder Genuine as needed. But I am not suggesting this is a definitive list, just one that suits me fine.

It should be clear by now that the colours you choose will depend on the kind of paintings you wish to make. You may be the kind of painter of revels in the use of bright highly saturated colours so these are the ones you will have to buy; you simply can’t mix them from any three primaries. On the other hand if you like a palette of muted subtle tertiaries then a box full of strident primary and secondary colours would be nowhere near as useful as a few well-chosen earthy colours with just a few of the necessary saturated ones (like my blues). In short you have to choose the colours you need to suit who you are, though I do appreciate that trying to choose from a rack of dozens of colours when you first start out can be a bit daunting. My advice would be to choose a single set from the ones I’ve mentioned and then modify it when you have more experience and get to know the sort of colours you prefer.

My next lesson will be about how to organise the painting of a watercolour, because although I appreciate that ‘anything goes’ some things can go better than others. See you soon.