Preservation and restoration is a profession devoted to the conservation of cultural heritage, such as works of art, for future generations. The activities involved in this profession include examination, documentation, treatment, and preventative conservation. The goal of the conservator is to attempt to maintain cultural heritage objects as close to their original condition as possible, for as long as possible. The conservator acts as a sort of steward for these objects, which range from archaeological to artistic.
The tradition of conservation is considered by most to have begun in 1565, with the restoration of the Sistine Chapel frescoes. During the 19th century, the fields of science and art became somewhat intertwined, and scientific processes were used to care for artistic objects. Today, all museums employ teams of conservators to keep their collections up-to-date, conduct frequent tests, and engage in analysis and documentation. In addition, numerous organizations create standardized methodologies for the conservation of art objects, such as the International Institute for the Conservation of Historic and Artistic Works and the American Institute for Conservation.
A painting, before and after restoration
This before-and-after image of a painting and frame exemplifies how art restoration can restore an art work to its original state.
The conservator's activities are guided by ethical standards. They must choose if, when, and how to alter a work of art in order to bring it closer to its original state. Since the original state is often beyond the conservator's lifetime, a certain degree of guesswork is required. Conservators are often involved in what is termed "preventative conservation," which refers to protecting art and cultural works from damage from environmental conditions, such as temperature, humidity, and exposure to light. This is why, for example, it is common to see textiles or photography exhibited in dimly-lit galleries.
A guiding principle of conservation is the idea of "reversibility"; that is, any intervention with the object should be fully reversible, and the object should be able to be returned to its original state. "Interventive conservation" refers to any act that involves a direct interaction between the conservator and the cultural material, such as cleaning, stabilizing, repairing, or replacing of parts. The conservator is required to fully justify any work of this sort and to complete documentation of the process before and after. Examples of interventive conservation include securing flaking paint and the tinted varnish treatment, whereby the restorer applies a tinted varnish over the original varnish, giving the illusion that spots on a work have been repainted.