In the mature works of the 1650s, Rembrandt was more ready to improvise on the plate and large prints typically survive in several states, up to eleven, often radically changed. He now used hatching to create his dark areas, which often take up much of the plate. He also experimented with the effects of printing on different kinds of paper, including Japanese paper, which he used frequently, and on vellum. He began to use "surface tone," leaving a thin film of ink on parts of the plate instead of wiping it completely clean to print each impression. He made more use of drypoint, exploiting, especially in landscapes, the rich fuzzy burr that this technique gives to the first few impressions.