Combination of FTIR and X-RAYS Synchrotron-Based Micro-Imaging Techniques for the Study of Ancient Paintings. A Practical Point of View

Applications of FTIR to the study of ancient paintings haveencountered two major steps: the development of FTIRmicroscopes, which enable to watch the sample and toselect the regions of interest; and the migration of thoseFTIR microscopes towards synchrotron facilities, thatoffers a significant improvement in terms of spatial resolutionand spectral quality. Even if access to synchrotrons isby nature limited, it is worth applying for such installationsas they usually provide a set of micro-imaging techniques.FTIR end-stations should then be considered as part of awider analytical platform. Combining micro FTIR with microX-ray fluorescence, micro X-ray diffraction or micro X-rayabsorption spectroscopy for the study of paintings enablesa deeper insight into paintings at the micrometer scale.Several examples of X-ray/infrared combinations are given.The focus is given to practical aspects, in particular to thecritical issue of sample preparation. Alternatives to theclassical polished cross-sections are proposed and evaluated.Data treatment is also discussed.