By Adam Gibson
A new multispectral imaging system was purchased by the digitisation suite in 2015, supplied by R B Toth Associates. One of the first objects we imaged was a music manuscript, supplied by Special Collections (MS FRAG/MUSIC/MSF1_MUSIC5). We acquired images under illumination from ultraviolet through colour to infrared and analysed them using principal component analysis.
The manuscript is believed to be 13th Century and contains Catholic songs, prayers and chants. It was dark (see Figure 1), but contained different colours so seemed a good initial test of multispectral imaging.
The bottom few lines are unclear so we looked at them in particular detail in figure 2.
These lines remain almost completely illegible, but there is an indication of a faint undertext. We analysed the 16 images acquired under different illumination using Principal Component Analysis, which collects the most interesting information across the 16 wavelengths into a smaller number of false-colour images. We chose the three images from PCA that best showed the uppermost text (Figure 3) and those which best showed the under text (Figure 4).
The uppermost text had already been identified as prayers, chants and a mass. The Gothic Latin text looks like "Libera me, Domine, de morte æterna" which is the opening of Libera Me, a Catholic chant said after the Requiem Mass. We're still unable to decipher the lower text.