Fig. 16

Detail of the cold painting in the Atelier window from the a internal surface, b internal surface seen from the outside (Spot 25). c OCT tomogram 50, registered from the external side, therefore through glass, showing the internal surface of the glass with a thick layer of cold painting (absorbing strongly) and an area of very strong surface scattering. Structures below the surface, thus visible in the area where air is expected, are multi-scattered artefacts indicating strong surface scattering, possibly related to detachments. Solid line: well-preserved cold painting. Dotted line: possible detachments