FAST AND NON-INVASIVE IDENTIFICATION OF BINDING MEDIA IN EASEL PAINTINGS BY A PORTABLE HYPERSPECTRAL SENSOR
A portable hyperspectral sensor collects reflectance spectra in the 350-2500 nm range, allowing the identification of not only inorganic but also organic materials. In this paper, a non-invasive and non-destructive characterization of pictorial binders was used. The results show that their main spectral differences are located between 1200-2400 nm. It is also indicated that when a binder is mixed with colorants, some modifications occur in respect to its original spectrum. In addition, the first derivative transformation of original spectra allows an easier identification of these organic binders, where the most discriminating regions are 1160-1250 nm and 1660-1800 nm.