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Since most of the things I draw are comic-ish/cartoony, there's no harm in practicing drawing some realistic portraits of some no of my friends

In my office the graphic designers were given assignments to practice digital painting from a photo reference. The boss is currently nuts over Makoto Shinkai artworks (he's got the art book which he passed around to us) & told us to follow  tutorials from McLelun . Photo reference: This one took me 2 working days.