*chiaroscuro, in painting, is a term used to describe the modeling of forms in light and dark, to provide the illusion of substance on a two-dimensional canvas, to add weight where there is none. chiaroscuro was perfected in the Italian Renaissance, and was a favoured technique of Michelangelo. Michelangelo Buonarroti, of course, was considered the highest master of the Italian Renaissance. His life is well documented, but I feel no shame in the liberties I have taken with it. I think he'd understand the need to give voice to a vision.
*Michelangelo Merisi da Caravaggio, known simply as Caravaggio, is credited with the invention of the tenebroso style, a dark space pierced by an emphatic stroke of light, which was adopted by artists including Rembrandt Van Rijn. It is generally accepted that he died in Naples, at the age of 37. He was an alcoholic, extremely violent, and flaunted his homosexuality, all to the dismay of the Church. An irrepressible non-conformist, Caravaggio's influence on art was profound despite the shortness of his career. One contemporary chronicler referred to Caravaggio as 'the anti-Christ of painting', an appellation which both delighted and frustrated him to no end.
*I am heavily indebted to Peter Robb, author of the magnificent biography M: the man who became Caravaggio, and to michelangelo.com, a web design company who pay admirable tribute to their namesake with the biography located here.
*lastly, sfumato is the smoky style of da Vinci, who does NOT figure in these stories, except as the spiritual father of all these men, yes, Methos included. :) It's my opinion, as an art historian, that da Vinci was instrumental in the development of modernity as it applies to painting, to philosophy, to science, to thought. His influence is still being felt today, and will continue to shape modern life. Without the precedents set by that 'absolute madman', not much of this could have happened.