I bought a drawing board today to help me in my project to design a pattern for a filet-crochet tallit. The tallit will be 36 x 72 inches, and I'm making the pattern half-size, which still means it's 18 x 36 inches and therefore pretty ungainly. The drawing board gives me a good surface to work on even when the table is laden with books, which is pretty much all the time.
The board was shrink-wrapped in a layer of plastic that was held away from the board's surface by the large clipboard-type clips on one end of the board. I strapped it to my bicycle's luggage rack and rode awkwardly home. Arriving home I stowed my bike in the back of the house, where the slanting rays of the sun illuminated everything. I realized that I must have leaned on the board to sign the charge slip when I bought it at the bookstore, because although the denting of the plastic that this caused was invisible, the sun was projecting my shadow signature out of nowhere onto the surface of the board.