Etching is a printmaking process that dates back 500 years. It involves sheets of metal, usually made of copper or zinc, and acid used to etch the print onto the metal. The artist can use complicated methods to create different effects, but always relies on acid to create an image on the plate. The more complicated the image, the more time consuming and expensive it will be.
To begin an etching, an artist must first coat a blank copper plate with wax. Using a steel needle, she draws her intended picture through the wax and onto the metal. The metal is then submerged into a bath of acid and left for about two hours. The acid will eat away at the copper that has been exposed by the needle to leave grooves, marks, and textures in the metal.
The plate is then taken out of the acid bath and the wax is cleaned off, leaving a shiny, copper plate with the image etched onto it. This can be repeated again and again by rewaxing the plate. By rewaxing, the artist can add layers or more complicated images onto the original drawing, then put it back into the acid bath once she is happy with the image she has.
The next stage of the process is to apply printing ink into the lines of the plate. Once the plate is wiped again with a stiff cloth, it will leave the ink in the lines and grooves. The inked plate is then placed in a hand-printing press with two heavy rollers, and damp paper is placed on top of the plate and squeezed through the rollers using great pressure.
When the paper is carefully peeled off, the image will be printed onto it. People can always tell a genuine etching because the edges of the plate will leave an indentation on the paper. If an artist wants to make another print, she simply puts more ink onto the plate, wipes it off, and then puts it back through the rollers with another piece of paper. The end result is the simplest form of etching.
There are more complicated ways to create more intricate etchings by using a number of different plates and colors. There is also a process to add different tones to the image that involves adding resin dust to the plate and heating it. The result looks like fine sandpaper, and the artist simply varnishes the plate wherever she doesn't want this texture. When she puts it in the acid bath, the acid will eat away at the resin dust to give a texture that holds the ink. The longer the plate is left it in the acid, the darker the tones will be.