I often use a colour wash on my paintings. The question I’ve been grappling with is “Why”. If I want the painting to be warm I use a warm wash and if I want a cold look, a cold wash. I know that the colour does show through a little. Acrylics tend to be more transparent so I would think the wash would show through more thus giving the work a warmer or cooler cast, but I don’t believe this is the major reason to do a wash. There are two reasons that I can see, the first is that it gives a solid colour that will show my sketching but the same is true if I sketched on the raw canvas or board. The second and I believe more important, is that it will influence all my colour choices throughout the painting process.