Many of the finest artists of contemporary times consider one aspect of art to be far and above the most important part of a strong piece. Without an understanding of value, we cannot create art that shows form or depth to a satisfactory degree, and our work will appear flat and dull. It's a huge subject, and an even more difficult one to master (something I will no doubt spend a lifetime trying to perfect myself) but a simple one to get a grasp of.
Put simply, value is the term we use to describe an objects relationship to light. Known also as 'tone', value communicates to us where an object sits on a black/grey/white scale. It shows us the form (3-Dimensional shape), depth and distance of an object. If line drawing is 2D, value is what we use to make our paintings come alive in three dimensions!
We will get into the mechanics of light and how it works next time, but for now, let's just figure out what it does, and how that applies to art. Light and shadow affect all that exists around us. It communicates much of what we interpret visually, and every single one of us has a deep and inborne understanding of it on an instinctual level. We will refer to strong light as 'high' value (closer to white) and 'low' value as darkness (closer to black). The overall composition of a painting will betray to us the light sources involved and their position, but more importantly, it can greatly influence the mood, intention and symbolism of an artistic work.
It's also worth noting that even in neutral light, every object has it's own inherent 'local' value. Colours exist on the value scale like anything else, hence why we refer to something as 'dark blue' or 'light green'. With this, we can predict (through practice) roughly where something will sit on the value scale even without seeing it in black and white. Because of this, if we remove all of the colour from the world around us, we could still exist quite happily within it, as value is the thing we use most to perceive the world around us.
A chiaroscuro painting (San Gerolamo by Caravaggio), upon removal of colour, we can inspect the individual local values of each object. Clearly, the white of the cloth and bleached yellows of the skull are higher on the value scale than that of the dark brown table, but note the warm tones of his skin in comparison with the red cloth.
The strength of the value of something is dependent on the strength of the light that falls on it. As we will explore more in depth later on, the side of an object that faces the light, will be lit relative to the strength of that light, and it's own local value. Therefore, if we place two identical objects side by side in the same lighting situation, the light that falls on them *must* be consistent. Likewise, if one object has a higher or lower local value than the one next to it, then that must be reflected in it's value. There is a 'cheat' that we can use to get a better grasp of this, which I will reveal in the next entry.