Explainer: what does an art conservationist do?

Cultural conservation is concerned with how cultural material is preserved as it moves from the past, through the present and into the future. This material may be books in libraries, documents in archives, objects or artwork in museums, or items owned by a community, a family or an individual.

It is the conservator's job to help ensure the material's protection and safe passage into the future for as long as is possible.

Art conservation is a complex and highly interdisciplinary task, requiring a knowledge base that may include methods of manufacture, the mechanisms of damage and the cultural significance of an object. Art conservators use history to understand why and when an artwork was made and science to understand how it was made and what has happened to it over time.

When the history of a painting is unclear, conservators will turn to art history to contextualise the work and to science to investigate the evidence of the date and method of manufacture.

Thorough examination and documentation is always the first step in conservation. This involves assessing the original structure and materials of the object, the extent of deterioration, damage and loss, and to ascertain previous restorations or other interventions.

Restoration and preventative conservation

The terms "conservation" and "restoration" are often used interchangeably, but they represent very different activities.

Restoration seeks to modify the appearance of an object to reduce the visual impact of deterioration or damage and to restore visual continuity. Although conservation may involve restoration, more usually it's engaged with preventing damage and deterioration.

Preventive conservation brings knowledge of the mechanisms of deterioration to provide the best options for the long-term care of cultural material. Take the example of a newspaper page turning yellow and brittle in the hot summer sun – knowing how the cellulose in the paper ages, that this process involves the creation of acid and that this acid contributes to the discolouration and deterioration of paper, means that appropriate steps can be taken to mitigate this process.

Preventative conservation is a predictive and holistic activity, often involving whole collections.

The operational aspects of air conditioning in museums are often the concern of conservators. Chemical and physical reactions involved in deterioration increase with higher temperatures and with cyclic changes in humidity. As a result, materials may crack or become brittle.

On one hand it makes sense to have continuous and stable air-conditioning; on the other hand, air-conditioning is energy-intensive and expensive to run. Understanding the issues, weighing the risks and advising on the best options for the collection is the job of the conservator.

Craftsmanship and ethics

Conservation also requires exceptional craftsmanship and art-making skills such as those employed in the original creation of the artwork; being able to replicate the paint layers, carve a section of an object to replace a lost part, or cast a sheet of handmade paper to use as a fill for a large hole are some examples of these kinds of skills.

There are also conservation-specific skills. The torn edges of a painting's canvas support may need to be rewoven thread by thread. A hole may require a patch which will then require a complex fill of the ground layer (the layer of gesso applied to the canvas to provide a smooth painting surface), paint and varnish that replicates the surrounding painting.

In some cases the painting's conservator will simple "tone" areas, adjusting the degree of lightness or darkness, so that the viewer can still read the extent of damage in the image. In other cases the conservator will make the image as complete as possible by "inpainting", reconstructing lost or deteriorated parts, so that the loss is virtually invisible.

Art conservation became a profession in Australia in 1973 and concerned at how best to support and develop programs for cultural materials conservation, the Australian Institute for the Conservation of Cultural Material (AICCM).

Under the AICCM's Code of Ethics and Code of Practice, any intervention by a conservator on an object has to be reversible – in practice, that means using materials and techniques that can be removed easily in the future.

That's one reason why an oil painting is never inpainted with oil paint. Oil paint cross-links with age until it forms a hard, plastic surface. In a few short decades a restoration done in oil paint will only be able to be removed with solvents that are strong enough to also remove the original paint.

This concept of reversibility is aligned to the concept of minimal intervention; and both require good documentation, usually a condition and treatment report accompanied by good images.

Because conservators are required to have a very deep knowledge about art and the way art materials age, their expertise is often sought when a work is suspected of being fake or misattributed. Authentication and attribution are complex activities that may have significant impacts on individuals or on the scholarship relating to a particular artist.

Conservators understand the long, silent and often invisible impacts of time and place. They are required to predict the sudden catastrophe that means instantaneous destruction.

Above all they are soothsayers, probing cultural materials to reveal the secrets of how and when they were made, and how they will survive into the future.

Robyn Sloggett, Director, Centre for Cultural Materials Conservation, University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.