Etchings and related Printmaking Techniques
Although today there are a wide range of alternatives to the traditional etching methods used by Howarth and his contemporaries, it is these that we will focus on here, as they formed the basis on which all of his work was produced.
Etching uses a technique known as Intaglio printing – the creation of a sunken relief in a flat surface - which is then inked to produce a final print on paper.
The basic method is to cover a metal plate (usually copper or zinc) with a wax coating (known as the ‘ground’) and then scratch the design or illustration into the surface of the wax with a metal tool. This exposes the copper where the wax has been removed and allows it to be etched.
The etching process involves submerging the plate into an acid bath, (Howarth favoured nitric acid) which then eats into the copper to produce the permanent sunken lines which form the master plate. This technique was historically known as ‘biting’ the plate.
The mastery of the technique involves achieving the required depth for each line, to produce a picture with graduated tones. The longer the copper plate is exposed to acid, the deeper the line is etched, and the darker the resulting line on the print, as a deeper groove will hold a greater amount of ink. Lighter areas of the drawing require less exposure to the acid.
It is not a ‘one shot’ process, unless the design is very simple, and can involve multiple immersions. In this instance, an initial period of biting lines will be followed by removing the plate and ‘stopping out’ these lines, by washing (to remove the acid) and then covering them over with wax or stopping out varnish to protect them from further biting before treating another part of the plate.
Once the lines of the plate are bitten to the correct depth, the wax covering is completely removed and the plate flooded with ink, which is then wiped from the surface, leaving the residue within the grooves of the plate.
Finally the plate is mounted in a press and positioned face down on a piece of paper. It is then placed under high pressure at which point the ink transfers to the paper to produce the finished print.
Experienced etchers can reduce the time taken to achieve a good plate, but due to the nature of the process, there remains a degree of trial and error to achieve a fine print.
The plate can be modified by burnishing to remove unwanted lines (polishing them out) or even modified by further work to form different variations from an original plate.
The etching technique allows multiple copies of a drawing to be produced, and many etchings are produced in limited editions before the plate is destroyed, making them collectable.
Because copper is soft, some wear occurs to the plate each time it is placed under pressure, with the result that eventually the fainter lines on it will begin to degrade. There are therefore a maximum number of prints which can be produced from each plate, although minor damage could be corrected by re-processing the plate.
Because of the pressure used to transfer the ink from the plate to the paper, the plate itself leaves an indentation in the paper, which is known as the plate mark.
Variations: – Other methods of Intaglio technique.
Drypoints are a variation on the basic etching technique which are worked dry – hence the name, and do not require the use of acid to etch the plate.
This technique uses a sharp metal point to produce a fine line in the plate, with slightly raised edges (or burrs) resulting on either side of the groove due to the cutting process.
These edges together with the groove in the plate act as a reservoir for the ink, and produce a darker, softer line than with etching. Because of the relative softness of the metal however, these edges become rapidly smoothed during the printing process due to the pressure employed, which means that the Drypoint technique is only useful for producing limited print runs.
Another variation in technique allows the production of Mezzotints. In this technique, the metal plate is scored across to initially create a rough surface. Those parts of the plate that will produce white areas on the finished print are then scraped smooth. When the plate is flooded with ink for the printing process, the ink is retained in the scored areas.
Mezzotints can be modified to produce a wide range of tonal effects by the use of different tools to create different scoring processes for certain parts of the plate. The amount of ink retained by the different areas produces the variety of tone on the print surface.
The technique was widely used from the mid 19th century onwards to replicate coloured pictures for publication as prints and in books and magazines.
Aquatints employ a variation on the above by using a resin covering to restrict the biting of the plate. The overall effect achieved is to simulate the style of a pen and wash drawing.
Originally developed from established engraving techniques, etching emerged in the early part of the 15th Century in Germany, where it became rapidly adopted before spreading to the rest of Europe.
German Artist Daniel Hopfer (c.1470-1536) from Augsburg was credited with its invention, and he applied the technique initially to decorate armour, and then later adapted it as a printmaking medium for fine art prints.
Goldsmiths and armourers would use acid etching techniques in conjunction with wax masking to decorate their products with intricate and attractive designs. This was a quicker process than the accuracy of cutting required for engraving, and could be done by those with drawing skills, but no formal training in engraving.
Because of this it was rapidly adopted by artists as a usable alternative to engraving, with the benefit of fine control over the depth of line and therefore the quality of the finished print. Not surprisingly, the widespread adoption of etching therefore triggered the decline in engraving.
As paper became more widely available, and the printing press and moveable type developed further etching was an obvious choice up until the middle of the 19th Century when it came to choosing a technique for replicating prints of fine art images to accompany the growing demand for books and magazines.