About this style: This style works for those who want a drawing that has a clean and technical look, and is a direct copy of the reference photo. It's also a safe choice, because there's a very small chance that the drawing won't look like you expect, and people will look most true to themself.
"Tracing" is a technique used to transfer an image into linework directly from photos. When I trace a photo, I draw (digitally) directly on the reference, to create a drawing as close to the original as possible.
It's like a direct copy, but outlined.
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(* or animals)