Figure 1

FTIR analyses of a 3μm-thick thin-section of a lead white model painting (lead white mixed with linseed oil, ratio: 0.5:1). The three spectra are a sum of 3 pixels selected in 3 maps acquired in 3 different acquisition modes, with SR beam: a) transmission mode (beam size: 10×10 μm², pixel size: 10×10 μm²), b) specular reflection mode (beam size: 10×10 μm², pixel size: 10×10 μm²), and c) ATR mode (beam size: 28×28 μm², with Ge crystal, pixel size: 10×10 μm²), on the right side is presented a visible light microscope image of the thin-section after ATR measurements, the dark central area represents contact region with Ge-crystal.