The Added Value of the 1.5–3 µm Band
Abstract (Format edited for easier online reading)
Infrared Radiation (IR) artwork inspection is typically performed through active thermography and reflectography with different setups and cameras.
While Infrared Radiation Reflectography (IRR) is an established technique in the museum field, exploiting mainly the IR-A (0.7–1.4 micrometers) band to probe for hidden layers and modifications within the paint stratigraphy system, active thermography operating in the IR-C range (3–5 micrometers) is less frequently employed with the aim to visualize structural defects and features deeper inside the build-up.
In this work, we assess to which extent the less investigated IR-B band (1.5–3 micrometer) can combine the information obtained from both setups. The application of IR-B systems is relatively rare as there are only a limited amount of commercial systems available due to the technical complexity of the lens coating.
This is mainly added as a so-called broadband option on regular Mid-wave infrared radiation (MWIR) (IR-C’/3–5 micrometer) cameras to increase sensitivity for high temperature applications in industry.
In particular, four objects were studied in both reflectographic and thermographic mode in the IR-B spectral range and their results benchmarked with IR-A and IR-C images.
For multispectral application, a single benchmark is made with macroscopic reflection mode Fourier transform infrared (MA-rFTIR) results. IR-B proved valuable for visualisation of underdrawings, pencil marks, canvas fibres and wooden grain structures and potential pathways for additional applications such as pigment identification in multispectral mode or characterization of the support (panels, canvas) are indicated.
Jeroen Peeters 1,* [OrcID] , Gunther Steenackers 1, Stefano Sfarra 3,†[OrcID] , Stijn Legrand 2, Clemente Ibarra-Castanedo 4[OrcID] , Koen Janssens 2[OrcID] and Geert Van der Snickt 2
1 Electro Mechanic Department, University of Antwerp, Op3Mech Research Group, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
2 Chemistry Department, University of Antwerp, AXES Research Groep, Groenenborgerlaan 171, B-2020 Antwerp, Belgium
3 Las.E.R. Laboratory, Department of Industrial and Information Engineering and Economics (DIIIE), University of L’Aquila, Piazzale E. Pontieri 1, Loc. Monteluco di Roio, Roio Poggio, 67100 L’Aquila, Italy
4 Electrical and Computer Engineering Department, Computer Vision and Systems Laboratory, Laval University, 1065 av de la Medecine, QC G1V 0A6, Canada
†Additional affiliation: Thermal Control Methods Lab No. 34, Tomsk Polytechnic University, Lenin Av., 30, Tomsk 634050, Russia.
*Author to whom correspondence should be addressed.
Received: 11 December 2017 / Revised: 28 December 2017 / Accepted: 29 December 2017 / Published: 1 January 2018
(This article belongs to the Special Issue Novel Ideas for Infrared Thermography also Applied in Integrated Approaches)
Peeters, J.; Steenackers, G.; Sfarra, S.; Legrand, S.; Ibarra-Castanedo, C.; Janssens, K.; Van der Snickt, G. IR Reflectography and Active Thermography on Artworks: The Added Value of the 1.5–3 µm Band. Appl. Sci. 2018, 8, 50.
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.