Q: I don’t know which white to use in my watercolors. How do you choose the right white?

A: Many traditional watercolorists will say the only white that should appear in a watercolor painting is the color of the paper—either untouched by the brush or showing through the layers of applied paint. With this method, a color is tinted strictly by diluting the amount of pigment applied to the paper. However, if you prefer to lighten areas of a painting by applying white, or by mixing a lighter shade of a tube color, the rule of thumb is to use Chinese white for mixing and titanium white for covering. The reason is thus: titanium white is a more opaque pigment and better suited for adding just a few light highlights to a nearly finished painting, while Chinese white is made with zinc oxide and is therefore more transparent.