Multispectral imaging of paintings

Identifying the materials of a painting is a crucial step in any conservation process. When the objective is to prepare an intervention plan, it is absolutely necessary to understand the matters the restorer is going to encounter. Also, when the aim is a better understanding of the artwork, and perhaps an authenticity check, it is highly relevant to know which materials were employed, since they may differ depending on the period of execution and on the specific artist as well. To identify materials on a painting's surface in a reliable manner, currently the most popular and trustworthy method is the analysis of microsamples of the paint layer. However, chemical analyses although reliable, have a number of drawbacks. The first is linked to the fact that this is an invasive method. The samples used need to be detached from the painting and will not be put back in place. Moreover, the achieved results are in principle - and often also in practice - valid only for that specific specimen and cannot generally be extended to neighboring areas.