I took a one day course not long ago on watercolour painting because I figured it would be a lot less material to cart around when travelling. Also, watercolour is a lot less messy and then there's the problem with acrylics in needing an easel and being able to place it in a good light. I realized at this course that I could actually use watercolour more or less the same way I use acrylics. It's certainly a reasonable way to paint since you seem to use so little paint.
Just to try it out I used a painting I had done in acrylics to copy.
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"Pines and Sailboats"
5 x 7 watercolour on paper
Nov/08
My original painting in acrylic:
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"View from the Pins Penches"
14 x 18 acrylic on canvas
2005