Masonite hardboards have smooth surfaces, compared to canvas boards which are textured. I find it easier to use hardboards when I want to apply thick paint so that the brushstrokes are visible. This technique is called impasto and was made popular by the Impressionists. I use Masonite hardboards for my 8"x10" paintings.
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Shy
8x10 inches, oil on Masonite hardboard
8x10 inches, oil on Masonite hardboard