Virtual reconstruction of the painting process and original colors of a color-changed Northern Wei Dynasty mural in Cave 254 of the Mogao Grottoes

Abstract

The Northern Wei Dynasty (386–534 CE) murals of Cave 254 in the Mogao Grottoes, China, have been extensively affected by pigment color changes and fading. These issues severely hinder efforts to correctly understand the value and painting process of murals from this historic period. The virtual reconstruction of the faded murals reflects the analysis results of the pigments applied during the painting process and provides a new direction for conservation and art research. However, simple virtual reconstructions may not be accurate owing to deficiencies in our understanding of the color-changed pigments and fading of image lines. In this study, multi-band imaging (MSI) was performed to obtain infrared-reflected false color, ultraviolet-reflected false color, and ultraviolet luminescence images of the mural. A portable X-ray fluorescence spectrometer, portable digital microscope, scanning electron microscope, energy dispersive X-ray spectrometer, liquid chromatography–mass spectrometer, and confocal Raman microscope were used. Non-invasive and minimally invasive analyses of local portions of different color areas were performed to identify their pigments and map the strata, and a hue–saturation–brightness palette was constructed for these pigments. Finally, the pigment analysis results were combined with the multi-band image features to determine the pigment distribution of the mural, which was then used to virtually reconstruct the original color and appearance of the faded mural under ideal conditions. This study is the first to use a virtual reconstruction based on objective analyses to simulate the original color, painting processes, and pigment stratigraphy of a mural from the Northern Wei Dynasty. A preliminary discussion of the relationship between the painting processes of the mural and color changes in its pigments was also performed. The findings of this study will provide new perspectives on the study of Northern Wei Dynasty murals.

Current progress on murals: distribution, conservation and utilization

“…In addition, based on pigments and physical strata of the murals from multi-band imaging techniques, it is possible to virtually reconstruct the original color and appearance of the faded murals. These technologies have been successfully used in some murals in the Mogao Grottoes in China [ 145 ]. The application of molecular and microbial technology provides deep insights into the processes and mechanisms of microbial deterioration of murals [ 146 , 147 ].…”

The Future of Heritage Science and Technologies: Papers from Florence Heri-Tech 2022

“…The Future of Heritage Science and Technologies: Papers from Florence Heri-Tech 2022 Rocco Furferi 1* , Maria Perla Colombini 2 , Kate Seymour 3 , Anna Pelagotti 4 and Francesco Gherardini 5 The nexus between cultural heritage and cutting-edge technology has exceptional prospects for understanding, preserving and enhancing the material legacy of humanity. Cultural heritage treasures can now be widely investigated and accessed thanks to advanced technologies.…”

“…To demonstrate the effectiveness of Multi Band Imaging (MSI), authors in Bolong et al [5], performed such a technique "to obtain infrared-reflected false colour, ultraviolet-reflected false colour, and ultraviolet luminescence images of the Northern Wei Dynasty (386-534 CE) murals of Cave 254 in the Mogao Grottoes, China". Moreover, they used additional analytical instrumentation, including "a liquid chromatography-mass spectrometer, confocal Raman microscope, scanning electron microscope, energy dispersive X-ray spectrometer, and portable X-ray fluorescence spectrometer".…”