X-ray radiography and IR reflectography
The research of painting techniques requires combination of information about the composition of materials together with the visualization of internal structure of the painting - usually provided by X-ray radiography and IR reflectography (both these methods are available in ALMA in high spatial resolution). Furthermore, it is nowadays possible to obtain these two types of information with one device. In ALMA, such device is represented by large area macro-XRF (MA-XRF) scanner, which provides maps of elemental composition in the entire area of the painting.
In addition, thanks to its higher penetration depth, lower layers are analysed as well. Therefore, MA-XRF scanning enables visualisation of older paintings (with different composition), and retouches and secondary interventions can be very precisely localized. The whole set of scanning techniques in ALMA is completely non-invasive and the integrity of the painting is fully preserved during the investigation.