Experimental study on merits of virtual cleaning of paintings with aged varnish.

To assess the accuracy of virtual cleaning of Old Master paintings (i.e. digital removal of discolored varnishes), a physical model was developed and experimentally tested using reflectance imaging spectroscopy on three paintings undergoing conservation treatment.

Complementary standoff chemical imaging to map and identify artist materials in an early Italian Renaissance panel painting.

Two imaging modalities based on molecular and elemental spectroscopy were used to characterize a painting by Cosimo Tura. Visible-to-near-infrared (400-1680 nm) reflectance imaging spectroscopy (RIS) and X-ray fluorescence (XRF) imaging spectroscopy were employed to identify pigments and determine their spatial distribution with higher confidence than from either technique alone. For example, Mary's red robe was modeled through the distribution of an insect-derived red lake (RIS map) and lead white (XRF lead map), rather than a layer of red lake on vermilion.