(CNN) -- Sigrid Avrillier might be a 65-year-old woman living in Paris, but for four hours each day she is transformed into the legendary Renaissance painter, Peter Paul Rubens. You wouldn't know it to look at her -- a former physics teacher with mousey brown hair and a cheeky gap-toothed smile. But over the last few months Avrillier has come to know Rubens intimately, recreating his every brush stroke, his every color choice. "I live with him," she says. "I become him." Avrillier is a copyist. And if you wander around the grand rooms of Paris' Louvre gallery, you'll see dozens of people just like her with their easels pitched in front of a masterpiece, paintbrush at the ready.
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Who are the Louvre's copyists and why do they do it?
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Since 1700s, artists have copied the gallery's masterpieces
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Famous copyists included Pablo Picasso and Paul Cezanne
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Today, just 150 copyists allowed, one year waiting list
"The children, they can't believe it," said @placeholder, who sometimes gives the youngsters a paint brush of their own.