From an artistic point of view, there are three basics properties of all colours: hue, chroma and value.
Those three are all we need to compare any two or more colours to each other, to decide which colours are harmoneous and which not and to understand the relationships between them and how those relationships influence the impact of our work.
There are far more sophisticated and specialized ways to handle colour, each with their own applications. Neither are hue, saturation and value enough to describe ALL the properties of colours1 – but for an artist that just starts out working in it, this is just enough.
Hue:
Hue is the colour of the colour itself.
Confusing? Well, not really. Hue decides if you have a red, green, a bluish red or a blue-green and well, all the other many hues the human eye can see. When people talk about colour they often mean hue, simply because it’s the defining attribute of a colour.
Saturation (Chroma):
Saturation and Chroma are two different concepts, but they’re so closely related that these two terms are often used interchangably. Both concepts describe how pure/vivid/colourful a colour is, even if the physics behind them differ slightly. For art usually one or the other is enough.
In the picture above, only the saturation of the colour changes, hue and value stay the same. Makes quite a difference, doesn’t it?
Anyways. Greys have zero saturation2, whereas the pure colours have the highest saturation possible. Ergo, the closer to grey a colour is, the less chroma it has. It’s important to keep in mind that the chroma and/or saturation of a colour has nothing to do with how bright or dark it is, because at least I tend to associate low saturation colours with dark values. But Pastels for example are bright but have low saturation.
Value:
Value simply describes how bright a colour is.
White has the highest value possible, black the lowest. This is the value: The lights and darks of your picture, ignoring saturation and hue of your colours. A greyscale photograph just captures the values of the photographed object, but not saturation and hue.
Value is sometimes really hard to see, since differences in hue and chroma can obscure a sameness in value. Take a look at the middle stripe of the image – it has the same value than the grey stripes, but it’s saturation shifts from no saturation at the black end to maximum saturation in the middle back to no saturation in the white end.
I have a real tough time eyeballing the value of any given colour. Kinda annoying, because getting the values right is often what makes or breaks a painting. But if you work digital like I usually do, turning the picture into a grayscale helps to see if the values makes sense.
A few final words
The relationship between hue, saturation and value can be quite a complex. It’s easy to accidentially change the value of a colour by trying to change the hue or to screw up the saturation while trying to brighten or darken a colour. And the only way to figure out what causes what is experience – or maybe a good teacher.
Working in colour is full of bootstrap (or “learning experiences”) like that and I’m not even half as good as I’d like to be.
Ah well, I’ll learn. Maybe this will help you, too.
Footnotes:
- Because in order to define all physical properties you need to start by differing between coloured light, coloured surfaces and how the human eye percives them. The sheer ammount of qualities you can/need to track gets confusing very fast. ↩
- Or zero chroma. That’s why greys are called achromatic and sometimes not counted as proper colours, my old art teacher was VERY insistent on that distinction. And in case it’s not clear, pure black and pure white do belong to the family of greys, too. ↩
Interesting to have something talking on colour. :) It’s useful to someone who continually thinks about starting to do art. :)
( Doubly so to someone who’s mildly colourblind. :D )
Yes, I found there’s a certain lack of completly-back-to-the-basics stuff around.
Most of the tuts seem to presume that you picked up a lot of knowledge just by osmosis and trial of error, but quite a few people who started out with art later in life just… didn’t; and for them the stuff that’s used to teach artists (even if it’S beginner-artist-level) is still confusing.
I hope to get some basics out here and there, which’ll also allow me to just link back to these posts if I throw around art-related vocabulary.
It also helps when someone just hasn’t paid any attention ever (until now), too. Picking up the basics quickly has to be helpful. :)
(PS: there’s a *lack of* back-to-basics stuff around? You accidentally the most important subclause.)
I do not know what you mean…
*innocent whistle*
I see what you did there.