What is sun fade, and what causes it?
Sun fade, also known as shading or ghosting, can occur when exposure to sunlight causes a surface to fade or darken. For example, framed art can prevent the wall treatment behind it from fading at the same rate as the rest of the wall because sunlight never reaches it. When the art is moved to a new position on the wall, a darker spot remains. The same thing can happen with an expression depending on its placement, the amount of light it receives, and the surface to which it is applied. Sun fading can happen to almost any surface regardless of the treatment applied (paint, fabric, stain, lacquer, and so on), but it is most common with oil-based paint. Sun fade is not caused by the material used in the manufacture of the expression.
