I don't know a tonne about the Preston Blair book, but it seems to deal mainly in teaching drawing for animation with standard cartoon character types as a guide. I've always kind of dismissed it for that reason, as I'm not interested in becoming an animator and I don't find the character types used in the book especially interesting. Likewise, I've passed by this hand page a few times and kind of assumed it wasn't for me as the hands have only 3 fingers and they're all gloved. However, I know that my drawings are sorely lacking construction and that this is a specialty of the Preston Blair course so I decided to take a whack at it.
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These hands were deceptively hard! I tried to follow the instructions and copy the examples on the page by following the steps at the top, but even with such simple steps it was difficult. Blair's hands have such zip and a really pronounced directionality that's hard to copy. I did my best, over 30 of them, but I'm still not a very good copier and I found it hard to loosen up at all. I learned a lot though, more than I have copying hands from pictures. The Preston Blair hands really start the thumb at the wrist, which is something I had never thought of before, and all the lines really follow the underlying shape , which makes the action really easy to read. My copies totally suck but I'm definitely going to keep this in mind from now on.
For those of you keeping track, we're at around 60. This is going faster than expected! If you have any hand resources you love, or you want to share your experience with the Preston Blair hands, please do let me know!