Varnishes can assist the art work in several ways. They can be used to change the surface gloss, making the surface more matte or higher gloss, or to provide the various areas of a painting with a more unified finish. They can also be used to increase color saturation. Varnishes offer protection for the underlying surface and allow for ease of cleaning of the painting or object. They are also often used to consolidate art work, in a similar manner to a fixative for charcoal or pastel. Some varnishes offer additional protection in the form of Ultra Violet Light Stabilizers, which dissipate UV radiation before it can contact the artwork where damage may occur. These varnishes are especially useful for materials that are fugitive in nature, such as dyes, but will not render them completely lightfast. The thicker the film of varnish w/ UVLS, the greater the protection afforded.