Fig. 7

a For the reconstruction paints of chrome yellow, measured reflectances of pure paint over white substrate are shown as dashed curves for chrome yellow lemon (blue) and chrome yellow (red). Solid lines show calculated reflectance of two types of chrome yellow as found in aged state on Field with Irises near Arles: chrome yellow as found in the field (blue), and as found in the yellow–brown dots (red). b Calculated Kubelka–Munk K (solid blue lines) and S values (solid red lines) for reconstruction paints chrome yellow (lighter colored line) and chrome yellow lemon (darker colored line). Dashed lines refer to published results from Levinson et al. [69]