The limits of colorimetry in cultural heritage applications

Colours in cultural heritage are not only means of expression, but also materials with physical and chemical properties. Since the beginning of the current century, colorimetry has become a fundamental field aiming at restoring, preserving and valorising the art works. There are different colorimetric applications in cultural heritage (eg, from light design to digitisation and modelling), and the variety of cultural material is extremely wide, from statues and frescoes, to old book and films. In this heterogeneous context, the development of instruments, measurements and tools faithful to the original objects are fundamental to correctly reproducing and representing materials, contrast and colours of the works under analysis. In this work, we will analyse the main limits of colorimetry applied in cultural heritage domain considering a variety of applications on physical colour representation and on digital colour reproduction. We will focus on main state‐of‐the‐art studies, regulations and guidelines for objects illumination, colour analysis and digitisation workflow showing some practical example of issues encountered by standard pointwise colorimetry.