I started out with a Pan Pastel underpainting, sprayed it with Spectrafix fixative, and then went in with the sticks.
First is the finished painting:
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© by Christine DiMauro, all rights reserved.
Here is the underpainting:
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© by Christine DiMauro, all rights reserved.
As you can see I ended up extending the bottom of the painting to show more bricks. That wasn't the plan, it just turned out that way. I tried to let some of the underpainting show through and it does, though not everywhere.
Here is a step mid way through the process:
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© by Christine DiMauro, all rights reserved.