Diane Arbus, Radical Photographer of the 20th Century

I've always liked artists' sketchbooks and planning/draft work. The book Revlations: Diane Arbus with her daughter Doon Arbus' commentary includes notebooks, letters, assignment briefs and other ephemera. You might be able to see a copy in a good bookshop's photography section.

Arbus used a twin lens reflex film camera that took large square negatives for her later work - the work mentioned in the OA. You look down into the viewfinder of a TLR and you see an image already framed and abstracted from your surroundings, and the perspective is that of an 8 year old (waist height camera position usually).

Arbus is one of my favorite phtographers. She was a pioneering woman photographer and a true artist.