Maurice Prendergast (1858-1924) was a masterful painter and colorist. His watercolor paintings have a beautiful shimmering luminosity, achieved through his transparent use of color and loose brushstrokes. His use of color is very much inspired by impressionist painters, like Claude Monet, who attempted to capture very exact moments of light. This atmosphere of light and color is created through the use of a "color world," painting with a very limited palette.
In each painting, Prendergast uses a variation of the primary colors (red, yellow and blue) as his base. I have identified the specific hues used for each painting so you can more easily see the palette he used. The three hues you see below the painting are the primary colors used in the painting. All other shades have been mixed from these three colors.
Try replicating one of Prendergast's color worlds in your own painting by using the same palette. Just remember, when using watercolor, when it looks like the color has been mixed with white, this just means that you are seeing more white from the paper showing through. The paint is made more transparent by mixing it with more water.