Pretty much just water. I attempted to use retarder but gave up as water and layering the paint on and also sometimes using a dry brush lightly over the canvas plus finger blending pretty much produces that result. I would also say that good quality thick acrylic helps a lot
that's sort of what I figured, I've done quite a few Acrylic paintigs so far, I only use extender if i have too, but mostly water and dry brush, but my printer is acting up, and I can't upload any more paintings, but check out what I got, let me know what you think, and What Acrylic brand do yo buy.
I absolutely love his expression in this shot. I think that was my favourite of all his many faces (except maybe when the hospital didn't blow up ). You captured the light of the scene perfectly, and he looks so real.
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Your art rocks!