Why varnish a perfectly good painting?
When I mention the word "varnish" in the context of applying it to a finished painting, I've often had a variety of responses from collectors, mostly in the form of alarm and concern. Many people imagine that I'm referring to the toxic, heavy duty stuff one applies to wood or metal to form a hard, clear, shiny surface. In fact, historically, varnish for oil paintings did tend to be toxic and a bit heavy duty, but that has changed as have many things over time and with advances in technology.
I have always felt that given how hard I work on my paintings and on development as a painter, the end product should maintain its quality and value from an archival perspective, which is what led me to varnishes. I learned about varnishing oil paintings in the course of my self-education as an oil painter, i.e. nerd-like studying of books, blogs and websites, and questioning more seasoned painters. Oil painting, aside from an aesthetic endeavor, also involves some minimal appreciation of chemistry. (Ironically, the requirement of an organic chemistry course ultimately dissuaded me from getting that minor in Biology during college!) An oil painting, when exposed to air and light, will change over time: the pigments will sink into the surface of its support, e.g. canvas, linen or board, potentially at different rates depending on how much and what kind of medium was used, and will be vulnerable to pollutants in the atmosphere. As a result, a painting will lose its original vibrancy and may appear to have an uneven sheen (i.e. shiny in some spots, dull in others). Varnish that is designed for oil paintings will overcome these issues.
The Old Masters had a couple of options, which are known as "traditional" or "natural" varnishes, that give paintings a rich, glossy, enamel finish, but yellow over time and can become brittle. A traditional option available today is known as Damar varnish, and it is an aesthetic choice for painters to use this type of varnish.
Alternatively, there are now a number of synthetic options which offer a number of benefits: they don't yellow and remain flexible over time; they can be removed fairly safely if a painting needs touching up; and one can control the level of shininess. I've become a huge fan of Gamvar, developed by Gamblin Colors in collaboration with the National Gallery of Art. It not only serves the purpose of traditional varnish, it is far less toxic for the environment and best of all you don't have to wait until a painting is completely dry (up to a year!) before you apply it (this is not the case for nearly all other varnishes).
Here's a short video of how it changes the appearance of a painting:
So, in summary, why varnish a painting?
- Provide a more unified finish to a painting
- Increase color saturation (i.e. return it to how it was originally conceived by the artist)
- Provide protection for the paint surface
- Allow for ease of cleaning
- Provide protection from UV radiation
- Change the surface finish to gloss or matte
I varnish all my finished paintings which gives me peace of mind that my paintings will have a better chance of surviving whatever elements they face in their new homes for many years to come. Ultimately, this provides added value to my collectors.
Let me know if you have any questions!