VARNISH A painting

You’ve painted a beautiful picture and you are ready to varnish it. But where do you start? LIZET DINGEMANS explains your options and shows you how it is done

- LIZET DINGEMANS

When it comes to varnishing a painting, there is a huge range of options available: exhibition varnish, retouching varnish, matte varnish, spray varnish… So, what do all these names mean? And are they really that different?

Varnish is a transparent layer meant to protect your painting from dust and grime, make it easier to clean (for both yourself and any future restorers), and deepen the colours, especially the darks. Depending on its composition, a varnish will dry to varying degrees of sheen, toughness and flexibility. In this article we will explore the different options as well as guide you through a step-by-step tutorial of how to varnish a painting.

The most common type of varnish is the traditional, resin-based varnish. These are made from combining a natural resin and a solvent (usually turpentine) to make it easier to apply. When the solvent evaporates, it leaves the resin on the surface of your painting. Common examples include dammar (or damar), a favourite of John Singer Sargent. It is very hard but may yellow over time. One common type of dammar-based varnish is exhibition varnish (or retouching varnish). This is designed to be used on a painting-in-progress to bring out dull spots and protect touch-dry paint. It is not meant to be a final coat, as it is much more temporary than normal varnish.

Other resin-based varnishes include shellac, which is obtained from trees and dries to a very hard, clear film. However, it can be expensive and isn’t suitable for vegans. Mastic is another sap-like substance which dries into a brittle resin with a semi-gloss finish.