From many moons ago, some dog studies from Preston Blair's book Cartoon Animation:
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From a couple weeks ago, a study from Jack Hamm's great book Cartooning The Head & Figure:
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From a couple months ago I think, I brought together some sketches I made while watching a Ren & Stimpy episode. Love the design of the droopy ghost:
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Lastly, from today, some studies from the manual of the video game Professor Layton and the Curious Village:
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I am going to make it a habit of not only putting the date on all the things I draw, but keeping track of how long I spent on each drawing. As you can see in the image, I spent 45 minutes on the full body Layton and 20 minutes on the closeup.