Raw Umber Sketchbook is the authentic surface of a prepared Old Master drawing sheet: a carta tinta ground brushed warm and darkened over four centuries into deep tobacco-brown laid paper. On it, raw-umber and bistre ink describe form, sanguine red chalk warms the flesh, and white chalk lifts the highlights off the tone. This is the working aesthetic of academic figure study — hatched, smudged, and fixative-stained — deliberately not a fresh cream page. Every mark assumes a middle-dark ground it can both darken and brighten against.