Multispectral and hyperspectral imaging technologies in conservation: current research and potential applications

Abstract

Spectral imaging technology, which records simultaneously spectral and spatial information about an object, was initially developed for remote sensing and has since been successfully applied to other areas of research. Although relatively new to the field of conservation, this non-invasive method of investigation has already provided promising results in the analysis of paintings and written documents, the characterization of materials and digital documentation. This article reviews the published literature relating to the application of multispectral and hyperspectral imaging for the study and conservation of works of art and presents some new perspectives offered by this innovative and fast-developing technology.

New insight on the underdrawing of 16th Flemish-Portuguese easel paintings by combined surface analysis and microanalytical techniques

“…-the results that reveal the use of iron gall ink in this workshop, which has a poor response in infrared reflectography not allowing the characterization of underdrawing under these conditions; -the recent studies based on DFT calculations using periodic boundary conditions on iron gall 3D coordination polymer which indicate that this compound has a maximum in its absorption spectrum at around 700 nm (Zaccaron et al, 2013a,b) and previous work on iron gall inks spectral absorption (Senvaitienė et al, 2005); -Previous studies based on multispectral and hyperspectral imaging technologies assessed on drawing inks (Baker, 1985;Kammerer et al, 2007) and easel paintings (Fischer and Kakoulli, 2006); we decided to refine the surface analysis methodology to perceive this type of underdrawing. Therefore, to capture the underdrawing executed with this material that had not yet been revealed by infrared reflectography, we used several bandpass filters coupled to an infrared photographic camera.…”

“…Another important aspect concerns to the style of the underdrawing, whether the underdrawing is a simple sketch, freehand or rather methodical and orderly. Finally, another important issue concerns to the identification of the materials and drawing tools used in the creation of the underdrawing (Bomford et al, 2002;Fischer and Kakoulli, 2006;Kammerer et al, 2007;Candeias et al, 2011).…”

An assessment of multimodal imaging of subsurface text in mummy cartonnage using surrogate papyrus phantoms

“…Multispectral imaging is an extension of standard digital photography whereby an object is illuminated sequentially under different wavelengths from ultraviolet to near infrared and photographed [15][16][17]. Blue and ultraviolet light may excite fluorescence of inks or substrates, so filters are used to exclude the illumination light, enhancing the fluorescent signal.…”

Optical Sensor Evaluation for Vision Based Recognition of Electronics Waste

“…A MS image can be described as the same image of one scene in different spectral ranges. MS imaging was originally developed for remote sensing applications and has recently found its way to the field of conservation [15]. In addition to its applicability for art conservation [16], the imaging technique has also proven effective for the analysis of historical and degraded documents [17].…”