Figure 1.

(a) Schematic view of a set of mockup paintings composed of: 8 single-pigment paint systems and a ground layer (namely carmine (1), vermilion (2), orpiment (3), minium (4), malachite (5), azurite (6), indigo (7), kaolinite (8), and ground layer (9)), and 14 mixtures using two pigment types (the mixtures can be split into four groups: (i) 7 mixtures of two colors composed of kaolinite white pigment and a non-white pigment with a 1:2 wt%, (ii) 4 mixtures of two non-white pigments with a 1:2 wt%, (iii) 1 mixture of three non-white pigments with a 1:3 wt%, and (iv) 2 overlays of two single pigment layers); (b) average reflectance spectra of all single-pigment paint layers applied on the prepared canvas; (c) pigment classification maps obtained using SAM; (d) pigment coefficient maps obtained using DNN model.