(1) (Color Key) See prepress proof. (2) Also called "chroma key," it is a technique for superimposing one video image onto another. Widely used to place an interesting scene behind people such as a ...

Paul Signac, Application of Charles Henry's Chromatic Circle; Théâtre-Libre playbill of January 31, 1889 Source: Paul Signac/Wikimedia Commons The nineteenth century was a tumultuous period in French ...