For the shading I was using the color wheel and experimented with three different colors on the same flower to see which I liked best. I was loosely thinking of an analogous complementary scheme:
- Select red violet (magenta) then count two more colors over to the right - violet and blue violet. Now choose a complement by putting your finger on magenta and following the line directly across the wheel to yellow green.
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Which do you like best? I'm thinking the dahlia purple... maybe the crimson red. I think the violet blue, a cool color, is not so good.