It is a sad fact that almost everything ages right from the moment it was created. Paintings do, however, age at different rates depending on the way they are constructed and with what materials, and then on the way that they are looked after.
Paint layers may dry and become brittle, eventually cracking; the oil itself can darken and varnish yellow; the pigments can alter in colour; oil paint becomes more transparent and underneath drawings may show through; the canvas may become brittle or weak, or slack; and the painting may become coated with a layer of dirt, nicotine, finger marks etc. Not all the effects of ageing necessarily impair our aesthetic enjoyment of the work of art, and while the pristine look of a painting as it may have left the artist’s studio is often the stated aim of a conservator or restorer, it will be better for paintings in the long term if we learn to live with some of the results of time acting on them.
Nevertheless there comes a time when paintings do need to be “restored”. The ravages of time may cause the painting to be unstable; it may suffer accidental damage; it may have been badly or insensitively restored in the past; or the dirt and yellowed varnish may just be too disturbing to enjoy the painting any longer. The owner of a painting can delay the moment when a conservator or restorer is needed and can help to slow the effects of time with good stewardship. I am presenting here a series of articles which will, I hope, help the collector to understand the work of the conservator, what he can and cannot do; what techniques he has at his disposal to analyse, repair, clean and restore a painting; how he can help to advise on the proper maintenance of a painting and on the provision of environmental protection even within a collector’s home. I will also explain how a painting is constructed and how and why paintings may become damaged.
Most conservation treatments will involve cleaning before the conservator can treat any damages. Due to the layer composition of paintings (eg ground, priming, paint layers, glaze and then varnish layer) a painting can become damaged by an unskilled conservator (for example someone who is not aware that a solvent originally intended to remove old yellowed varnish could be removing original glazes). A good conservator will, after cleaning, retouching any losses of paint with a paint medium which will remain reversible and, the conservator will use the minimum intervention necessary to pull the visual aspects of the composition together. Documentation of each stage is essential so future conservators can be aware of the painting’s history.
An object’s owner may be put off by much of this but it is worth remembering that the object will be well treated and last for many centuries to come. The results of treatment look superb at first and only time will reveal the quality of the work. The owner should also consider whether there is a need to clean a painting; simple removal of surface dirt usually significantly improves the overall appearance of a picture, an aged and yellowed varnish may conceal an over cleaned or badly damaged painting. The removal of a dark varnish may thus reveal the poor condition of the painting which may involve a complete retouching programme which has added cost implications. Removal of a discoloured varnish will also change the painting and it will no longer be the picture the owner knew.
The most important thing an owner can do is to look after his paintings. Ensure excess light and UV light and humidity fluctuations are minimised and make sure the painting is free of nicotine and open fire smoke as these can all increase the rate of deterioration of a painting. Check the hanging mechanisms and ensure pictures are light with conservation grade lighting.