For many painters the word “scumble” indicates a thin, brushy application of paint applied with a dry brush––and that is an accurate use of the word.
Scumble, however, can also refer to a thin layer of opaque or semiopaque paint applied over other colors, and it’s the second definition that applies to glazing.
The effect of scumbling with white is threefold:
- It lightens values.
- It lowers chroma, thereby making the underlying color less intense.
- It slightly cools the temperature of the underlying color.
A scumble also inserts a degree of opacity, creating an excellent base for subsequent layers of transparent, glazed color.
To read more about glazing, see Koo Schadler’s entire "Brushing Up" column in the September 2006 issue of The Artist’s Magazine.