The Thumbnail Challenge
"Thumbnail sketches” are small, preliminary sketches used to work out composition, tonal balance other areas that can make the painting process problematic. They can be used to explore the effect of adding or subtracting elements in your painting without committing time and paint to a large sheet of paper.
Before starting a painting it's a good idea to make some compositional sketches, because planning makes the painting process easier.
In all the books I've read on the subject the thumbnail sketches had been made in pencil and I had avoided doing them for this reason. However, once I began using watercolour to paint them I found them to be both enjoyable and useful.
By identifying the largest shapes and the longest lines first, you can then add only what is necessary to suggest the characteristic of the object or scene.
1. Do I want a landscape, portrait or square format?
In the thumbnail sketches above I was working out which format suited the subject matter as well as where to place the main divisional lines - see tutorials on Design and Composition and The Focal Point.
2. Where do I want to place the main divisional lines?
For example; in a landscape painting, do I want to show more foreground (high horizon line), or more sky area (low horizon line)? But this applies to any subject matter.
3. How can I simplify the scene?
By reducing the scene to as few shapes as possible concentrating on large shapes only. By squinting you can identify areas that are similar in tone and incorporate them into one shape. No need to put in any detail at this stage. Next, shade your sketch using as few tones as possible. Try only three or four tones. For example, paint a medium tone wash, leaving the white of the paper as the lightest tone, and then paint in a dark tone.
This exercise forces you to look at the subject as a simplified pattern of light and dark shapes. In doing so you can plan the overall tonal relationships in your painting.
In the examples below I used four tones, and having identified the main areas of tone, I tried reversing the tonal pattern which seemed to change the time of day these might have been painted in.
Other tutorials that may be of interest prior to making thumbnail sketches are:-
Planning a Painting