If you want to really understand your subject, do a value study before you paint it in color. Pick a color you like that is dark enough to give you a range of 3 or 4 values. In this example, I’ve used ultramarine, other good choices include burnt umber, burnt sienna, Prussian blue, alizarin crimson, or any other favorite of yours that is dark enough.Force yourself to translate the colors of the subject into pure values, this is very challenging particularly if your subject is very colorful and has colors that are close to one another in value. In the example above, the reflections in the water are very complex, I’ve used values suggest and simplify the reflections of the trees on the water. Doing this helps you to understand how the values in the subject relate to one another. When you use your value study as a guide, painting in color is much easier. If you are working in oils or acrylics, the value study can serve as your under painting. For watercolor or any other transparent media, a separate value study is needed.
Have fun with it, challenge yourself with different subjects and lighting and use different colors to do each of your studies. It’s an interesting exercise that is sure to improve your ability to see value relationships!