Being able to paint colour that creates a convincing impression of light and shadows is not easy. Especially when you’re starting out.
A few years ago, it consumed more of my easel hours than anything else. And I couldn’t understand why it was so hard.
I mean, the colours were right there in front of me. I could see them. Why couldn’t I just paint them?
Why is it so hard?
Often people will say that colour is hard to get right because of simultaneous contrast: The colours around a colour affect how we perceive it.
And that is part of the story.
But more than that, our perception of a colour is affected by our assumptions.
If we know a colour is in shadow, we will assume it’s much darker than it actually is – because our brains are used to interpreting colour. It’s how we function in the real world, how we navigate through space and see a three dimensional world.
We need to know that a yellow in shadow is still a yellow, no matter what the perceived colour is.
It’s why the white patch at the back here in shadow here appears so much brighter than the corresponding one in the light at the front. In fact they’re exactly the same.
But we think it’s lighter. Because we know it’s in shadow. We know that it could only appear that light if it was actually giving off light.
So that’s what our brain makes us see. And squinting down to see values can help, but if you squinted at this, you’d still see the patch of white at the back as lighter.
And you’d be wrong.
A lot of the time, we just can’t trust the assumptions our brain makes about what colour something is.
Hue, value and chroma
Most people think hue changes from light to shadow across forms. It doesn’t, much (but there is a caveat, which I’ll get to at the end of this post).
Everybody knows that value changes, that’s pretty obvious.
But very little attention is given to how chroma changes across a form.
In fact, mostly what changes across a form from light to shadow is value and chroma, and if you can do a good job of getting both right, you will create a convincing feeling of depth, light and form – and your colour will look right.
But how can we do that when we’re so bad at just judging colour accurately by eye?
Well, it starts by understanding what hue, value and especially chroma really are.
What is chroma?
Here’s a quick (1 and a half minute) video with an explanation of Munsell (where hue, value and chroma come from) showing what hue, value and importantly chroma are:
So how does chroma change?
It follows something I call the chroma curve. Because if you plot a simple graph of how colour changes in both value and chroma, you get a curve.
Let me show you what I mean.
Firstly, here’s a pic of the set up I used for the photos I’m going to use to explain this.
Left of the easel is a cube and a sphere in a shadow box. On the easel is a drawing board with a page from the Munsell Book of Colour stuck to it.
Both the cube and the sphere were painted with a single colour from that page (although, a slightly different one for each).
The colour the cube and sphere are painted is called the local colour.
Judging colours accurately
Now, to get around the problems of simultaneous contrast and the troublesome assumptions of our brains, we need to take the colour out of its context and to see it by itself.
The simplest and most effective way to do that is to use an isolator – just a grey piece of card or paper with a hole in the middle, like this (I’m also holding a Munsell chip to compare the colour to in this pic):
The local colours
The first thing you need to know is what the local colour of something is. If you paint a cube or a sphere yourself, that’s easy because you chose the colour 🙂 (it’s also one reason why Munsell is SO useful for an exercise like this – you know exctly what hue, value and chroma the local colour is too).
So the local colour of the cube corresponds exactly with this chip in the 5YR page from the Munsell book.
The sphere is this colour:
The perceived colours of the cube:
If I use an isolator to judge the average colour of each of the three faces of the cube, I find they correspond very closely to chips on the page from the Munsell book:
So if I mix those three colours up and get them right, I can paint a good, lifelike version of this cube just with those colours (and some for the background and foreground, of course).
You can also use the isolator to check your mixes, by putting a little dab of your mixed paint on a piece of card and holding up against the isolator, as I was with the Munsell chip in the earlier photo.
But this is important: If you try using an isolator like this, the key is to always hold it parallel to your painting surface – at the same angle to the light. Otherwise you’ll judge the colours all wrong and it won’t work.
The chroma curve for the cube
If I draw a line between those three colours, I get a rough curve like this:
Notice that the value and the chroma are changing, but the hue isn’t.
OK, fine. But what happens when I’ve got a more complex subject than a cube?
It will really help you when painting form to think about the main 5 modelling factors. You can see them fairly clearly on a regular sphere, and whilst they obviously bleed into each other and cross over, if you can find an average colour for each you can paint light and shadow pretty convincingly.
The perceived colours of the sphere
Taking a rough average for the main modelling factors, and using the isolator, I can judge the colours I’ll need to paint a convincing sphere pretty accurately.
Notice something missing?
I’ve only included four modelling factors. I haven’t included the reflected light here in order to keep things more clear, but usually, if I were painting a study, I’d include it.
The chroma curve of the sphere:
If we plot a line between those colours on the Munsell page, we get something much closer to a curve this time, because we have more points to work with.
The beauty of this is that if we mix up those colours, we can find all the other colours we need by simply mixing between them, and we won’t mess up the hue.
Now, assuming an object of a single local colour, this curve will always stay true. If the object has a shiny or a matt surface, the shape of the curve will change, but it will still be a curve.
If this sphere was painted a lower chroma colour of the same value and hue, the curve would look like this:
Can I do this without Munsell?
Well, kinda. But Munsell just makes it a lot easier. In fact, I would say that the main reason Munsell is so useful is that it allows you to control hue, value and chroma independently of each other.
It also allows you to see what really happens to the hue, value and the chroma as a colour goes from light to shadow in the real world.
You don’t have to listen to wild theories about using complements to paint shadows (which will look really, really wrong unless you’re painting impressionism outside)
You can still learn about this without Munsell, just less effectively.
Try setting up a sphere in a shadow box and use a colour isolator and a little strip of plastic or card to check your mixes. Without a Munsell reference you won’t be able to see what’s happening at the same level of detail, but it will teach you a huge amount about how colour changes across a form.
Why bother with all this?
Because knowledge makes you better at stuff. No really, it does.
If you know how the colours you perceive change from light to dark you can start to make intelligent choices about how you use colour in your work.
Also, if you paint imaginatively, knowing this will help you hugely – you’ll be able to paint convincing colour without having any kind of reference in front of you.
What was that about hue?
Ah yes, I almost forgot. I’ve found that hue changes very slightly as colour moves into shadow, usually in an anti-clockwise direction.
The hue of the shadow of orange objects will pull slightly towards red. For yellow objects,it will pull towards orange. For blue ones, towards green. (I haven’t tested magenta and purple yet). But it’s very, very slight.
How do you know all this?
This has come from a lot empirical studies and testing. It’s what I’ve found after putting in a LOT of hours painting different forms and judging the colours of their lights and shadows, and plotting them in the Munsell book.
So I’m passing it on to you. You have the entirety of my method here, so you can go and find your own answers to the questions of how to paint form. You don’t have to take my word for it. In fact, I hope you don’t, because we learn much more completely by actually doing.
And it may even seem a dull way to spend your easel time. But if any of these questions have ever vexed you as you paint:
- what colour is that shadow, really?
- how much darker is it than the light part?
- Why does that shadow I’ve just painted look wrong?
- how can I make this look more real?
- mix any colour accurately
- see the value of colours
- lighten or darken a colour without messing it up
- paint with subtle, natural colour
…then this method will show you the answers.
Of course there’s more to painting form really well – edge handling, considering the surrounding values, value manipulation and compression, sound drawing etc etc. And if we widen the question to the making of art, we consider design, meaning, on and on.
All I’m talking about here is the colour – the bit that foxes most people. If you can get this bit right, then you can move on to the more interesting stuff more quickly.
On Wednesday 2nd May 2018, at 9PM UK time (4PM Eastern, 1PM Pacific) I’m giving a free webinar on all this stuff.
I’m going to paint some spheres live to show you in detail how this all works. And whilst I’m at it, I’ll show why some common approaches don’t work too.
There will be a live chat so you can ask questions as we go along. These things are usually lots of fun too, since you get to hang out with a bunch of other painters of all levels for a bit, albeit virtually.
There will be a recording if you can’t make it live, so register anyway and send you out a link to it when it’s done.
Best wishes and thanks for reading!
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