Oxgall Liquid is a traditional wetting agent used to decrease surface tension in transparent watercolor and gouache.
It also increases paint flow and can be used to create washes.
Play with and test what oxgall will do in a watercolor wash!
In this test strip, we made washes with and without the liquid—both applied to the paper, to the water and to the paint.
The most dramatic results occured with a drop of oxgall added into a wet wash of Pyrrol Orange—the color moved, creating a smooth, gradated wash.