Fig. 5

Comparison of the reflectance spectra obtained from spectral imaging for the text and the illumination on folio 83r: a spectra for the ink of the text (black circle and A28 in the inset) and the outline of the architectural motif (red circle and A23 in the inset); b spectra for the blue text (black circle and A5 in the inset), blue illumination (green circle and A11 in the inset) and reference azurite (blue cross); c spectra for the red text (black circle and A4 in the inset), red illumination (magenta circle and A8 in the inset) and reference vermilion (red cross); d the dark shadow of the red architectural motif (red circle and area A4 in the inset) and the Kubelka–Munk model fit (black cross) to the mixture of spectra of the black text (A14 in the inset) and the red text (A13 in the inset)