Have been experimenting with watercolour on canvas. The canvas, wood, metal, or whatever you want to paint on is first coated with a transparent or opaque watercolour ground. The surface then accepts watercolour paint. It reacts quite differently from paper as it does not soak into the surface. It is easy to pick-up colours to make lighter areas and if one does not like the result it can all be washed off, recoated, and painted again.
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