This led to me asking a docent a question which led to an really interesting, to me, answer. I love
the Dutch painters of the 17th century, their 'Golden Age' and I was always fascinated by their ability to produce amazingly life-like detail in fabrics, feather, animals hair, etc and yet their rendition of human and animal faces was much less skilled. The docent told me that many of these painters worked, not from life, but from pattern books of animal faces and quick sketches of their subjects, perhaps done by others. So they could have swatches of fabric (velvet, brocade, etc) and pose them in the exact light they wanted to copy the effects but they had only sketches of the faces to go by.
"Karel Dujardin 001" by Karel Dujardin - The Yorck Project: 10.000 Meisterwerke der Malerei. DVD-ROM, 2002. ISBN 3936122202. Distributed by DIRECTMEDIA Publishing GmbH.. Licensed under Public domain via Wikimedia Commons -
File:Karel Dujardin 001.jpg - Wikimedia Commons
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"Willem van Aelst - Bloementuil" by Willem van Aelst (1627after 1682) - Unknown. Licensed under Public domain via Wikimedia Commons -
File:Willem van Aelst - Bloementuil.jpg - Wikimedia Commons
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