The definition of tonal values in art is how light or dark something is on a scale of white to black. White is the lightest value and black the darkest.
Tonal value is one of the most important aspects to painting. It is the value structure of a work that allows us to be able to see light and dark in a painting. Value is even more important than color when it comes to learning how to paint. One can mix the most beautiful paint colors, but if the values are incorrect then the painting will not work. The opposite is also true. For example, if the colors are ‘incorrect’ but the values are then the painting will work.
Tonal value scale
Here is what is called a value scale for tonal values. It is a system to organize values ranging from white to black. As you can see #1 is white and #8 is black. The shades of grey that are in between make up most of the value shades in a drawing and or painting. It can be an extremely helpful tool for painters to identify light, middle tones and darks more easily.
High keyed and low keyed tonal values
Depending on how much black or white a value has it will appear lighter or darker in value. The tones toward the lighter end of the spectrum (those with more white in them) are termed ‘high keyed’ in value. Those values on the darker end of the spectrum (with more black than white in them) are termed as ‘low keyed’.
In the illustration above you can see a clear illustration of the high keyed values versus the low keyed values.
High keyed painting
The Seurat painting above, Bathers at Asnieres, is an excellent example of a painting that is ‘high keyed’. Most of the values used in the work are from the ‘high keyed’ end of the value scale spectrum. However, there are of course some darker elements present such as the pants and hat of the lounging man. One will nearly always find at least some darker elements present in a high keyed work. Just as there are always light elements present in a low keyed work.
Low keyed painting
The painting above by Diego Velazquez can easily be considered a low keyed work. Most of the values present are from the low key end of the value scale. When you compare the Seurat painting against the Velazquez painting you can get a clear picture of what a high key work looks like compared to a low keyed work.
Now, we will go over how light and dark values apply to paintings and real life lighting situations. It is important to understand these principles as values are a central element to painting. Without a basic understanding of values you will not be able to capture a sense of light.
Illustrated here is a diagram depicting the distribution of light and shadow and the different types of lights that are present. If you want to create a believable sense of light then you need to pay attention to these aspects of light and shadow.
Halftone – Form light is divided into halftones that darken as the form turns away from the light surce
Core Shadow – As reflected light loses strength, it creates the core shadow
Form Shadow – This is the part in shadow
Penumbra – The softness around the shadow
Cast Shadow – This shadow is the terminator projected on the ground
Occlusion Shadows – Where two surfaces get close to each other, a dark shadow forms
Reflected Light – Light on the dark side of the form that is reflected onto the form by another surface
Terminator – this area divides form light and form shadow
Form Light – The area that receives direct light
Center Light – The area that faces most directly towards the light source
Light effects applied to painting
Here is an applied example of what the different aspects of light look like on a painting by Thomas Eakins. As an exercise you can look at paintings by the great masters and find where the halftones are, dark lights, center light, reflected lights etc.
Here is another example of light distribution in Rembrandt’s ‘Portrait of Johannes Wtenbogaert’. You can see here an expert example of what halftones, light, dark and cast shadows look like in a master painting.
Make a value study
The best way to learn about values is to take some artist charcoal or woodless graphite pencils and start to make some value sketches by yourself. Also, working on making monochromatic drawings is a great way to start understanding dark and light values. Once you add color into the mix it is much more difficult to figure out values!
Here is a tonal portrait drawing I did of my brother. It is a simple brief drawing that captures the basic essential values. When you work on creating tonal drawings/ sketches try to simplify the values as much as you can.
Again, here is another example of a drawing that has simplified values. There are no more than 4 values present. Light value, light middle tone, dark middle tone and a dark value.
What is next in the study of values?
The study of light and dark is a huge topic and cannot not be fully explored in one article. Next up learn how to create drawings with light and shadow.