this project is a precursor to a painting project involving color theory
and schemes. my students had to create a value study first, (graded
separately)...the photoshop filter (posterize) really separates those
values nicely. great lesson to help kids who might lack confidence in
their abilities to shade. technically, it isn't really shading, as i
tell them, but as they find that full range of values, it's easier for
them to "fill in the gaps", visually speaking.