Lose the drawing:

to use the sketch as a map that will not be visible in the final rendering, scan drawing and clean up as necessary to see the important details. Develop a series of layers that introduces color, value, details, and texture.

Reveal the drawing:

uses a similar workflow as technique A, but employs layer opacity and blend modes settings that allow the drawing to be seen through the rendering. Favorite settings include the Multiply layer blend mode on either the drawing or the renderings- whichever is sitting higher on the layer stack.

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