A: Innenstadt, Köln, Nordrhein-Westfalen, Germany, B: Amsterdam-Centrum, Amsterdam, Noord-Holland, Netherlands
In 1642 German soldier and amateur artist Ludwig von Siegen invented the mezzotint process of printmaking. Mezzotint was was the first tonal method of printmaking, producing prints that have a more painterly appearance. The word derives from Italian meaning "half-painted." Von Siegen's first known mezzotint is a portrait of Amelie Elisabeth von Hessen.
Mezzotint allows "half-tones to be produced without using line or dot based techniques like hatching, cross-hatching or stipple. Mezzotint achieves tonality by roughening the plate with thousands of little dots made by a metal tool with small teeth. In printing the tiny pits in the plate hold the ink when the face of the plate is wiped clean. A high level of quality and richness in the print can be achieved."
Wax, The Mezzotint. History and Technique (1990) 15-16.