Aquatint

Aquatint is an intaglio printmaking technique, a variant of etching.

In intaglio printmaking, the artist makes marks on the plate (in the case of aquatint, a copper or zinc plate) that are capable of holding ink. The inked plate is passed through a printing press together with a sheet of paper, resulting in a transfer of the ink to the paper. This can be repeated a number of times, depending on the particular technique.

Like etching, aquatint uses the application of a mordant to etch into the metal plate. Where the engraving technique uses a needle to make lines that print in black (or whatever colour ink is used), aquatint uses powdered rosin to create a tonal effect. The rosin is acid resistant and typically adhered to the plate by controlled heating. The tonal variation is controlled by the level of mordant exposure over large areas, and thus the image is shaped by large sections at a time.

Another tonal technique, mezzotint, begins with a plate surface that is evenly indented so that it will carry a fairly dark tone of ink. The mezzotint plate is then smoothed and polished to make areas carry less ink and thus print a lighter shade. Alternatively, beginning with a smooth plate, areas are roughened to make them darker. Occasionally these two techniques are combined.

The painter and printmaker Jan van de Velde IV invented the aquatint technique in Amsterdam, around 1650. The cartographer Peter Perez Burdett later introduced his 'secret' aquatint technique to England in the 1770s. In the United States the printmaker Pedro Joseph de Lemos popularized aquatints in art schools with his publications (1919–40), which simplified the cumbersome techniques, and with traveling exhibitions of his award-winning prints.

An aquatint requires a metal plate, an acid, and something to resist the acid. Traditionally copper or zinc plates were used. The artist applies a ground that will resist acid. Ground is applied by either dissolving powdered resin in spirits, applying the powder directly to the surface of the plate, or by using a liquid acrylic resist. In all forms of etching the acid resist is commonly referred to as "the ground."

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