Pencil Drawing Tutorial - Yunoko
Step 1
Paste an image on your canvas.
Step 2
With the image selected click on Filters>Others>Find Edges. The image is darkened with the lines highlighted.
Step 3
Go to the Properties window below the screen and click on Blend Mode and select Difference.
Step 4
Click on Filters>Sharpen>Sharpen. The lines appear a little darker.
other examples:
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