Identification of the historic photographic print materials using portable NIR and PCA

摘要

This work presents an investigation of 98 black-and-white historical photographs of three type of binders (albumen, gelatin, and collodion). The work is aimed to differentiate photographic processes using an effective approach of near-infrared (NIR) spectroscopy combined with the multivariate statistical method of principal component analysis (PCA). Methods, e.g., detrending and normalization, processed the dataset of 882 spectra. The PCA results were compared with the method of attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. This comparison indicates the chemometric approach as a very perspective to examine historical photographs in a fast and non-destructive fashion.