High-resolution hyperspectral imaging (HSI) utilized a fully integrated camera and lighting system to capture information and images in 13 spectral bands from the non-visible and visible regions of the spectrum - including ultraviolet, visible and infrared wavebands from 365 nm – 1050 nm. A 39 megapixel MegaVision monochrome camera integrated with an Equipoise LED low light, low heat lighting panel system (including raking or side-lighting panels) is integrated with software to capture a cube of images with associated metadata parameter files. The images in this ‘image cube’ can be digitally combined with or subtracted from each other to form images for precise analysis. The spectral imaging allows characterization of substrate (paper, parchment photographic processes) and colorants (dyes, pigments) based upon their specific spectral response. These specific spectral responses from compounds discriminate between similar materials and compounds, identifying and possibly quantifying materials present in the image.
HSI allows the establishment of baseline data where deterioration assessment techniques can be linked to micro-analysis.
The accurate determination of parameters associated with inks, pigments, colorants and base materials over time from a baseline response without sampling is critical to the assessment and preservation of many international items of cultural heritage.
Applications:
- establishing baseline images and spectral response data for deterioration studies, treatment evaluations, and monitoring fading/deterioration during exhibit
- non-invasive characterization and mapping of past treatments on documents
- non-invasive characterization and imaging of pigments, inks, and colorants
- revealing text or images that have faded or been covered up, using advanced processing of data from discreet wavebands
Example project: Integrated Digital Imaging Systems: Hyperspectral Imaging
Hyperspectral Camera System.
