Technique

In the printmaking process the printing plate is first covered with a layer of acid-resistant ground made of various waxes, gums, and resins. The ground is often darkened, usually with the smoke of lighted tapers; this aids the visibility of the process of drawing the design, which is done with an etching needle into the ground, thus clearing a path through to the printing plate, which is immersed in a bath of acid.

The depth of the lines is determined by the strenght of the acid and the length of time the plate is therein. Plates can be wholly or partially ‘rebitten’ by further immersions. Parts of the design can be selected for further ‘bitings’ by covering over or ‘stopping-out’ those sections of the design considered to have been sufficiently bitten already.

Once ‘biting’ has been completed, the acid-resistant ground is cleaned off and the plate is inked up and printed from. The more deeply bitten the lines the moredistinctly they print.

AQUATINT

It's a technique that allowds to obtain different gradation of gray and light-and-shade effects.

As in etching, the zinc or copper plate is bitten by the immersion in acid. Granules of acid-resist laid on the plate result in a fine, reticulated patterning when the plate is inked and printed from, thus producing an effect not unlike a wash.There are two distinct methods of aquatint.

In the first a dusk-box is used to blow particles of resin onto the plate.

In the second the resin is dissolved in alcohol which is brushed over the plate; as the alcohol evaporates, particles of resin are left on the plate. The artist can vary the tones of different parts of his aquatint by subjecting them to bitings in the acid-bath of different duration. The parts he wishes to print relatively light in tone can be protected by coating with stopping-out varnish, resistant to acid, those that are to print darker can be rebitten.