Lighting the world's treasures: Approaches to safer museum lighting

A strategy is reported to optimize lighting to reduce photochemical degradation of works of art and archival documents. The strategy revolves around improving luminous efficiency of the spectral profile to exclude light which doesn't contribute to brightness or color perception, while also trying to maintain color rendering. The work focuses on Old Master Drawings and designing filters for illuminants, but is applicable to the broad range of art and archival documents and the direct design of lighting without filters such as LED. A filter profile is identified which seems to be beneficial, or at worst neutral for all pigments measured. Underlying principles are identified: (1) The best luminous efficiencies arise from multiple band illuminants, and also improves as color rendering is sacrificed. (2) Protection of an object even late in its damage life can significantly extend its remaining life. (3) Protection of an object early in its life can possibly abate some of the light induced damage it may experience across its life, so early intervention in light protection may be advised. This report further goes on to suggest approaches to further enhance the protection, including tailoring the spectral dependence of appearance change.