Optical fibers for safer exhibition conditions in museums: the measurement of equivalent-light dose

摘要

Works of art exposed to excessive lighting suffer from color changes due to photo-oxidation or photo-reduction of the pigment/dye. Chromatic damage to artworks is not only the result of exposure to overly intense light, but can also be caused by the combined action of light with other environmental factors such as thermo -hygrometric variables and pollutants, which can amplify and accelerate photo-alteration. Therefore, the prevention of chromatic damage requires measurement of the equivalent-light dose, i.e., the dose capable by itself of producing a color variation, without the contribution of other environmental factors. The system presented in this work performs a continual measurement of the equivalent-light dose so as to indicate the potential for chromatic alteration of the exhibition environment. Experimental results are presented, that were obtained during continual measurements over 300 days, part of which at the Uffizi Gallery of Florence.