Special capturing presentation at the Croatian Conservation Institute

2023. 06. 30. | News


On 22 May, the Croatian Conservation Institute (HRZ) organised a presentation on “Multispectral Recording of Cultural Heritage” in the Hall of the Museum Documentation Centre, where the most specific recording of cultural heritage digitization was presented by our digitization specialist and Phase One expert, Dániel Bedő.

The event was organized with the participation of the Croatian Institute of Restoration, the Croatian State Archives, the Ministry of Culture and Media of the Republic of Croatia, the Strossmayer Old Masters Gallery HAZU, the Museum Documentation Centre and the Faculty of Graphic Arts in Zagreb. The presentation examined canvases and archival documents in both visible and invisible spectra.

Multispectral technology also demonstrated on site: the PhaseOne Rainbow

The “PhaseOne Rainbow” process allows the use of multiple multispectral imaging technologies in a single camera system. The idea is to use light sources that illuminate at different light levels and appropriate filters to display information invisible to the human eye in digital images. For example, the machine can be used to detect signs of human fluid, fingerprints or weapon use during a crime scene investigation. The technology can also be used for a variety of purposes, for analysis or authentication in the fields of art history and forensics. It can be used to make texts in poor condition legible and to analyze polychrome surfaces (paintings, stones, other materials) or any other tissue (for example, to determine the material and age in historical research).

During imaging, the filter discs that are part of the camera system, as well as the different light sources, are automatically switched on and off under the control of the equipment’s own software, called Rainbow MSI. The process takes a few minutes and produces 8 images. The system is capable of automatically adjusting the sharpness according to the wavelength, so that imaging is uninterrupted. The multispectral technology allows a non-invasive, non-intrusive method of examining the object being analysed. It is necessary to take 8 images each time, as the human eye is not able to decide in which light spectrum the information relevant to the research or authentication process can be detected.

Using different wavelength light sources and special filters, the artworks were captured using the following techniques:

  • IRR (near infrared reflectography)
  • IRRFC (near infrared reflectography false color)
  • UVIL (ultraviolet induced infrared luminescence)
  • UVL (ultraviolet induced visible luminescence)
  • UVR (ultraviolet reflectography)
  • UVRFC (ultraviolet reflectography false color)
  • VIL (visible-induced infrared luminiscence)
  • VIS (visible reflected)