Portrait conservation: Bringing the eighteenth century to today

Anna Cuyler VanSchaick before conservation

When we look at paintings, what we’re doing is getting a visual glimpse at the past from someone who lived it. Paintings provide valuable information on how people lived their lives, what they wore, what they did, and much more.

But have you wondered why old paintings always look like someone’s applied a yellow filter and turned the lights off?Over the years, these historical snapshots become clouded from sitting in houses or storages. Years of wear and tear, dirt and varnish, attempted overpainting, and unsuccessful repairs darken the painting and cover fine details. 

So then, what’s to be done?

Behind the scenes, many methods go into making sure nothing is damaged and the painting is restored to be as close to the original as possible. 

For varnish and surface material making the portraits look dark, solvents are applied. Many things can be solvents, and many act differently, but the main purpose of any solvent is to dissolve something else. Have you ever seen someone remove permanent marker from a whiteboard by spraying it with something that made the marker runny? That was a solvent! Conservators do a very similar thing to the dirt and oil stuck to the painting. The molecules in the special solvents they use are shaped in a way that lets them stick to the oil molecules and pull them right off the painting’s surface while leaving the dried paint behind. Once the top layer is a liquid, it can be easily soaked off with cotton or a gentle sponge, leaving behind a bright and clean original layer of paint.

Over time, the original paint can flake off as well. In some cases, the missing patches are left alone. In others, previous conservators replaced the holes with their own paints, guessing as to what may have been lost from the initial work. Today, x-rays and ultraviolet lights help identify different layers and types of paint, allowing the conservationist to see what the original painting definitely showed and what may have been improvised from someone else’s attempt at repair. 

And sometimes, conservation methods get...less conventional. Many mid-1900s conservation efforts used melted beeswax to strengthen the portrait and attach second or third canvases behind the first for support. Fortunately, these days there are much better materials for conservationists to use. Unfortunately, for some paintings, this wax has to be removed first before the painting can be re-backed. 

How do they do it? 

Edward Collins as a Youth, during conservation treatment.

They heat the painting! Sort of, anyway. Heating a painting at moderate temperatures allows most of the wax to melt and stick to a blotter paper instead of the canvas. The rest can then easily be taken off with a simple solvent. Science!

If you want an example, take a look at this Edward Collins portrait on the left. An early conservation in 1958 coated the painting with resin, tried to patch some damage, and added a cardboard backing. However, when the museum acquired it, the resin had darkened, the surface was uneven, and a hole had appeared. Modern conservation relined the portrait, re-painted areas, and used a combination of tissue paper, the solvent xylene, and cotton to clean the surface. And in the end, the effects speak for themselves - the conservation significantly brightened the piece, making it look much closer to how it was originally painted, and even uncovered an previously illegible inscription under Collins’ figure!  Take a look at the slideshow at the bottom of the page to view the painting before, during, and after treatment.

So the next time you browse art at AIHA, from thirty or three hundred years ago, and consider the work put into it and the history behind it, also appreciate the care, effort, and innovations taken to preserve the piece - you wouldn’t be looking at it in its current state without it!

Author: Zeroun, Junior Interpreter