My aquatint Towards the Forest has been selected for the Royal Academy's Summer Exhibition, so I thought I'd write something about how aquatint prints are made.
Aquatint is a technique used to create a tone in intaglio printmaking. Tiny particles of rosin powder are melted onto a metal etching plate and when the plate is placed in acid, the metal is eaten away (bitten) between these dots, which resist the corrosion. This creates something that will hold ink on the plate which, when printed on to damp paper with an etching press, will appear on the paper as a rich mark similar to watercolour.
The shade of the tone created depends how long the plate has been exposed to the acid. By painting varnish (stopping out) on to the plate to prevent areas being bitten further, and working in stages from light to dark by putting it in acid many times, a whole range of tones can be created. The bite is cumulative, so if you put the plate in the acid for ten seconds, stop out an area, and then put it in the acid again for 20 seconds, when you remove the varnish you'll have a lighter area (ten seconds) and a darker area (30 seconds, because it had already been bitten for ten seconds before the second bite). Writing down the times for all the different stages is essential, because it's easy to get confused!
I love this technique because it you can create painterly effects but it also has that magic of printmaking where you never know for sure how it's going to look until you print it. Using the aquatint process is exciting, challenging and gives a wonderful depth of tone.