Blind Contour Drawing

It is a great definition about Blind contour-from Wikipedia
Blind Contour drawing
Blind contour drawing is a method of drawing, popularized in part by Kimon Nicolaïdes in his book The Natural Way to Draw (1941), which presents itself as an effective training aid or discipline. The student, fixing their eyes on the outline of the model or object, draws the contour very slowly in a steady, continuous line without lifting the pencil or looking at the paper. The student may look at the paper to place an internal feature, but once they begin to draw it, they do not glance down, but follows the same procedure as for the outline. A well-done blind contour drawing frequently has sufficient quality and character to be preserved as a work of art.
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