Thank you for your informative response. Since craquelure is part of oil painting, do today's artists use a more stable medium?
I just saw the movie "Girl with a Pearl Earring" and became entranced by the portrait. It has been restored twice but the craquelure remains. Wish I could see it as it was on the day Vermeer finished. In fact (and this will horrify you), I would buy a print if they could airbrush out the crazing.
You know how old oil paintings are covered with a network of fine cracks? I'm wondering why restorers don't try to repair this crazing in the paint. The "Girl with the Pearl Earring" would look much more like a girl if she didn't have all those "wrinkles".
Is it possible to reverse/prevent this crazing in oil paintings? How long does an oil stay smooth--one year? Ten? A hundred?
Dear Janet, Your questions refers to the general term "craquelure" which is part of the natural drying process of oil paint. There are a number of terms used to identify various appearances of surface cracking, such as cupping, alligatoring, spider webbing, etc. All drying oil paint shrinks and causes craquelure, this can occur in a matter of weeks or a hundred years. The volume and type of crazing is affected by how the support (canvas, wood panel, composite board, etc.)was prepared, and the recipe of the paint medium. The support is usually covered with a layer of gesso, plaster, or white lead paint, which is called the "ground". After this dries or ages the artist then applies his paint, or may first draw a sketch and then apply his paint. The paint pigments are suspended in an oil base which can be "personalized" by the artist. He may add any of numerous solvents, oils, or even bitumen to make his paint thinner, thicker, or his colors more opaque or more translucent. All of this will affect the drying of the paint, and the type and amount of craquelure.
Painting conservators can often eliminate or lessen the distracting appearance of craquelure. Before painting conservation became a science people would attach a second canvas to the back of the original with glue or white lead and press it with heavy weights. This would flatten the cracking, but also flatten the impasto and pretty much ruin the painting. Today, depending upon the type of craquelure and its cause, conservators will use different types of backings to reduce the craquelure. One method is to use a vapor treatment on a vacuum table, which relaxes the original paint surface and reduces the crazing. Sometimes the only way to improve appearance is to fill in the cracks and repaint those areas. However, this is done sparingly and only when there is no other option. In some cases it is safest just to live with the painting as it is.
Dear Janet, I answered this question some time ago, but evidently it did not go through. Most painters today use acrylics which seem to be more stable than oil paints, however in my opinion they lack the warmth and depth of oil paint. Also, acrylics have not been around long enough to know how they will appear in 100 or 200 years.