A Hidden Portrait by Edgar Degas

Abstract

The preservation and understanding of cultural heritage depends increasingly on in-depth chemical studies. Rapid technological advances are forging connections between scientists and arts communities, enabling revolutionary new techniques for non-invasive technical study of culturally significant, highly prized artworks. We have applied a non-invasive, rapid, high definition X-ray fluorescence (XRF) elemental mapping technique to a French Impressionist painting using a synchrotron radiation source, and show how this technology can advance scholarly art interpretation and preservation. We have obtained detailed technical understanding of a painting which could not be resolved by conventional techniques. Here we show 31.6 megapixel scanning XRF derived elemental maps and report a novel image processing methodology utilising these maps to produce a false colour representation of a “hidden” portrait by Edgar Degas. This work provides a cohesive methodology for both imaging and understanding the chemical composition of artworks, and enables scholarly understandings of cultural heritage, many of which have eluded conventional technologies. We anticipate that the outcome from this work will encourage the reassessment of some of the world’s great art treasures.

Reflectance imaging spectroscopy and synchrotron radiation X-ray fluorescence mapping used in a technical study of The Blue Room by Pablo Picasso

“…The detector was developed jointly at Brookhaven National Laboratory (Upton, NY) and CSIRO (Clayton, VIC, Australia) and is described in detail elsewhere [24,25]. Previous models of this detector have been successfully applied to elemental mapping of other works of art [26,27].…”

MA‐XRF study of 15th–17th century icons from the collection of the National Museum in Krakow, Poland

“…For example, Romano et al reported a lateral resolution of up to 25 μm, scanning at a speed of 100 mm s −1 with 500 μm pixel size . Thurrowgood et al presented 31.6 megapixel high‐definition XRF mapping using synchrotron source . Moreover, studies concerning improvements to large data files acquisition and processing have been gaining importance, as has the coupling of MA‐XRF with other techniques, for example, hyperspectral imaging, X‐ray absorption spectroscopy, or optical coherence tomography …”

CRONO: a fast and reconfigurable macro X‐ray fluorescence scanner for in‐situ investigations of polychrome surfaces

“…Until recent times, micro‐ and macro‐XRF mapping/imaging analysis was possible only by synchrotron radiation requiring the transport of precious artworks to large scale facilities . Only in the very last years the advancement in instrumental technologies has made it possible to transpose the technique to laboratory and to in‐s itu applications .…”

“…[7,8] Until recent times, micro-and macro-XRF mapping/imaging analysis was possible only by synchrotron radiation requiring the transport of precious artworks to large scale facilities. [9][10][11] Only in the very last years the advancement in instrumental technologies has made it possible to transpose the technique to laboratory and to in-situ applications. [2,3,12,13] However, finding a good compromise which takes into account instrument portability, large scans, beam dimension, count rates, and acquisition time is still very challenging.…”