*3.1. Visible Light Micro-Reflectance Spectroscopy Analysis*

Sample D816-4, which derives from a pink-reddish area, presents a characteristic reflectance spectrum (Figure S1a, Supplementary Materials) where a first weak maximum is visible at 466 nm, followed by an increase of reflectance starting at 540 nm; the sigmoid curve presents a marked inflection point at 581 nm, while another one is observable at 690 to 695 nm. A less-defined inflection point should be present at 432 nm, but the individuation is not easy due to the higher noise at around 400 nm (lower intensity of the lamp emission). The related apparent absorption spectrum (Figure S1b, Supplementary Materials) presents a maximum at ~550 nm, with a shoulder at ~510 nm. A lower intensity band is observable at ~670 nm. The sample D816-9 presents similar features (Figure S2a, Supplementary Materials): the reflectance is the same in the 400–500 nm range, but it starts increasing around 510 nm with a complex trend. Indeed, several inflection points are observable, as highlighted from the first derivative spectrum. In particular, an inflection point is still

visible at 560–580 nm, while, from the first derivative, the other ones should be present at 425, 617, and 648 nm, confirming the complexity of the spectrum. In the apparent absorption spectrum (Figure S2b, Supplementary Materials), there is a variation in intensity for the bands at 510 and 550 nm: the first one is more intense than the second, while a new low intensity band is observable ~600 nm. The band at 670 nm is not visible, whereas a new band is visible at ~690 nm.

In addition, for the sample D816-7 (Figure 2a), corresponding to a green-blue area of Rama's skin, the reflectance spectrum obtained complex results: two weak reflectance max- ¯ ima are observable around 480 and 600 nm, while an increase of reflectance is observable over 615 nm, with an inflection point at 669 nm. With reference to the derivative spectrum, another inflection point is present at 651 nm, while less defined ones could be present at 431 and at 500 to 525 nm (the second results in a very flat maximum in the derivative spectrum). The corresponding apparent absorption spectrum presents a main maximum at ~643 nm, with a minor flat band around 500 nm (Figure 2b).

**Figure 2.** (**a**) Visible light reflectance spectrum obtained for D816-7 sample with the corresponding first derivative (red lines highlight the inflection points) and (**b**) related apparent absorption spectrum (background subtracted).

The reflectance spectra obtained for the samples D816-5 and D816-15 do not present informative features (Figures S3 and S4, Supplementary Materials): the reflectance is very low, increasing without any evident spectral feature, and the spectral noise is remarkable. The related first derivative spectra are characterized by continuous oscillations and high noise, not allowing for a clear identification of the inflection points. The apparent absorption results in a spectrum where the presence of characteristic signals is not evident. Only a very low intensity band at around 690 nm is observable after background subtraction, but it cannot be excluded that the processing could be responsible for the artifacts in this case. The absence of clear absorption signals could be in agreement with the black color of the extracted dye.

For the S¯ıta puppet, the FORS spectrum acquired for the D817-2 sample presents a ¯ first reflectance increase over 410 nm, reaching a maximum at around 470 nm and followed by a great increase from 525 nm. The reflectance slope decreases over 600 nm, while, in the first derivative spectra, the inflection points are observable at 424, 570, and 655 nm (Figure 3a). In the apparent absorption spectrum, a defined band is centered at 530 nm, with a broadening at around 490 nm, while a low intensity broad band is visible at 680 nm (Figure 3b).

**Figure 3.** (**a**) Visible light reflectance spectrum obtained for the D817-2 sample with the corresponding first derivative (red lines highlight the inflection points) and (**b**) related apparent absorption spectrum (background subtracted).

The D817-4 FORS spectrum presents a more complex behavior: the reflectivity (Figure S5a, Supplementary Materials) increases over 403 nm, the slope seems to decrease around 470 nm only to grow again over 480 nm; a second decrease of the slop is observable at 640 nm, but the reflectivity increases again to over 650 nm. The first derivative spectrum highlights an inflection point at 440 nm and a second one at 550–560 nm, but the features of the obtained derivative spectrum are less clear in comparison to the previous case. In the apparent absorption spectrum, two broad bands at 506 nm (with shoulder ~540 nm) and at 674 nm are observable (Figure S5b, Supplementary Materials).
