Periodic Reporting for period 2 - CHANGE (Cultural Heritage Analysis for New GEnerations)
Reporting period: 2021-05-01 to 2023-04-30
Objects of tangible cultural heritage inevitably change over time, demonstrating alterations to materials’ appearance, due to structural or chemical degradation, human interventions, or simply environmental deposits. Documenting, understanding, monitoring, and interpreting these changes are crucial to their preservation and the retention of their values.
The CHANGE project has trained a new generation of 15 Early Stage Researchers (ESRs) towards a common goal – assessing the changes of tangible cultural heritage using state-of-the-art multimodal imaging techniques in complement to the more traditional analytical techniques. Novel methodologies for data registration, image processing and visualisation have been implemented directly on CH objects to characterise and evaluate degradation processes and conservation-restoration treatments. The project aimed to take CH digitisation to a new level by exploring digital datasets for deeper analysis and interpretation.
CHANGE has focused on several key objectives within three scientific work packages (WP) presented in the next section.
Conclusion of the action:
The project has provided methodologies and systems to analyse and monitor changes in cultural heritage objects. By addressing the challenge of change capture and tracking, the methods, and multimodal protocols ESRs have developed ensure the accurate registration of data while excluding acquisition errors. Based on imaging technologies, non-contact and without deteriorating fragile artworks, several modalities and cross analysis were used to improve data quality and reproducibility, allowing for effective tracking of changes over time. Methods developed in CHANGE are proven efficient on several object types, e.g. glass, wall painting, gilded wood and were applied to monitor several restorations processes. This new knowledge will be valuable for conservation and digitisation of cultural heritage and these pioneer systems and protocols will enter into daily practices in conservation of cultural heritage.
The CHANGE project has trained a new generation of 15 Early Stage Researchers (ESRs) towards a common goal – assessing the changes of tangible cultural heritage using state-of-the-art multimodal imaging techniques in complement to the more traditional analytical techniques. Novel methodologies for data registration, image processing and visualisation have been implemented directly on CH objects to characterise and evaluate degradation processes and conservation-restoration treatments. The project aimed to take CH digitisation to a new level by exploring digital datasets for deeper analysis and interpretation.
CHANGE has focused on several key objectives within three scientific work packages (WP) presented in the next section.
Conclusion of the action:
The project has provided methodologies and systems to analyse and monitor changes in cultural heritage objects. By addressing the challenge of change capture and tracking, the methods, and multimodal protocols ESRs have developed ensure the accurate registration of data while excluding acquisition errors. Based on imaging technologies, non-contact and without deteriorating fragile artworks, several modalities and cross analysis were used to improve data quality and reproducibility, allowing for effective tracking of changes over time. Methods developed in CHANGE are proven efficient on several object types, e.g. glass, wall painting, gilded wood and were applied to monitor several restorations processes. This new knowledge will be valuable for conservation and digitisation of cultural heritage and these pioneer systems and protocols will enter into daily practices in conservation of cultural heritage.
After a four-year project period has ended, the Early Stage Researchers’ work have been demonstrated through several publications and presentations at various conferences. At the time of writing, 46 journal and conference papers have been published, and several are under peer-review. The papers are openly available in Zenodo repository together with data sets collected and analysed for the research (https://change-itn.eu/dissemination/publications/(opens in new window)). Most papers have been presented at various conferences and results have been disseminated and communicated through various media like social media, website, videos, brochures etc.
Some of the results for the three scientific work packages (WP) are presented below:
WP3: Multiscale and multimodal strategies and systems for change capture and tracking of cultural heritage assets: in this WP the ESRs have been working on finding methods and strategies on how to select devices to characterise change in appearance of different materials as different materials encounter different challenges. E.g. stained glasses are transparent, they can easily reflect light, and they are often placed far up in the historical building they are part of – all aspects that make it challenging for imaging. ESR 1 has studied, developed, and tested methods (laboratory, portable, in-situ) to optimize the digitization of stained-glass windows in different scenarios. ESR 8 has developed a robotic arm based RTI acquisition system, a setup to automate and expedite acquisitions while capturing cultural heritage surfaces, allowing the generation of images with light from many different angles, trying to overcome the challenge of shadows covering details when capturing textured objects.
WP4: Computational methods for change studying (characterization, visualisation, and monitoring) of Culture Heritage assets: For the data of change detection to be useful, it is important to find methods to visualize them. Two novel methods for further post-processing of surface data to identify the location of changes and assess them over time or before and after conservation treatment on heritage objects have been implemented by ESR 4. ESR 3 had developed a method for cross-time registration, where 3D models captured at different timeframes, or before and after a modification, are aligned.
WP5: Application: Change during the alteration and conservation of cultural heritage artefacts: What are the needs of a cultural heritage actor when using imaging techniques to monitor artefacts during their alterations? This is one of the questions we have tried to answer in this WP. Together with a conservator, ESR 7 has tested gloss measurement for imaging to quantify appearance changes when removing varnish of gilded painting and frame using various methods, including traditional colorimetry, gloss measurements, and bidirectional reflectance measurements. The varnish removal method was chosen based on the results of this test.
The ESRs of CHANGE have received training in using imaging techniques, multivariate data analysis as well as change measurement. In addition, they have received training in transferrable skills important for their research careers, like research ethics and project management. This was conducted during training schools at the NTNU in Norway, at C2RMF and UBFC in France, HES-SO and SNM in Switzerland, WUT, AFAW and MKJ in Warsaw in Poland, as well as at the Rijksmuseum in the Netherlands. All ESRs have set up a personal career development plan as well as a data management plan with focus on generating open data, increasing the possibilities of exploitation of the CHANGE results.
The ESRs have also conducted several stays (secondments) with different project partners during their project period.
Some of the results for the three scientific work packages (WP) are presented below:
WP3: Multiscale and multimodal strategies and systems for change capture and tracking of cultural heritage assets: in this WP the ESRs have been working on finding methods and strategies on how to select devices to characterise change in appearance of different materials as different materials encounter different challenges. E.g. stained glasses are transparent, they can easily reflect light, and they are often placed far up in the historical building they are part of – all aspects that make it challenging for imaging. ESR 1 has studied, developed, and tested methods (laboratory, portable, in-situ) to optimize the digitization of stained-glass windows in different scenarios. ESR 8 has developed a robotic arm based RTI acquisition system, a setup to automate and expedite acquisitions while capturing cultural heritage surfaces, allowing the generation of images with light from many different angles, trying to overcome the challenge of shadows covering details when capturing textured objects.
WP4: Computational methods for change studying (characterization, visualisation, and monitoring) of Culture Heritage assets: For the data of change detection to be useful, it is important to find methods to visualize them. Two novel methods for further post-processing of surface data to identify the location of changes and assess them over time or before and after conservation treatment on heritage objects have been implemented by ESR 4. ESR 3 had developed a method for cross-time registration, where 3D models captured at different timeframes, or before and after a modification, are aligned.
WP5: Application: Change during the alteration and conservation of cultural heritage artefacts: What are the needs of a cultural heritage actor when using imaging techniques to monitor artefacts during their alterations? This is one of the questions we have tried to answer in this WP. Together with a conservator, ESR 7 has tested gloss measurement for imaging to quantify appearance changes when removing varnish of gilded painting and frame using various methods, including traditional colorimetry, gloss measurements, and bidirectional reflectance measurements. The varnish removal method was chosen based on the results of this test.
The ESRs of CHANGE have received training in using imaging techniques, multivariate data analysis as well as change measurement. In addition, they have received training in transferrable skills important for their research careers, like research ethics and project management. This was conducted during training schools at the NTNU in Norway, at C2RMF and UBFC in France, HES-SO and SNM in Switzerland, WUT, AFAW and MKJ in Warsaw in Poland, as well as at the Rijksmuseum in the Netherlands. All ESRs have set up a personal career development plan as well as a data management plan with focus on generating open data, increasing the possibilities of exploitation of the CHANGE results.
The ESRs have also conducted several stays (secondments) with different project partners during their project period.
Digitisation and analysis are important practices in the cultural heritage sector; however, it needs more in-depth and standardised tools/strategies for perform accurate documentation and further exploitation of the data. The needs and expectations of cultural heritage actors have evolved profoundly over the past decades by highlighting the alteration phenomena and their monitoring versus time. Detection, monitoring, and characterisation of changes in cultural heritage artefacts requires the need to collect precise information on both shape and appearance changes. This not only helps to understand the mechanisms developed but also to control them better to minimize the changes. Within the CHANGE project change analysis based on a multi-modal approach that can be applied at various scales has been conducted, guided by the needs of cultural heritage actors. It has been an interdisciplinary and rich framework to train Early Stage Researchers in technology, methods, and conservation/ restoration. The tools, methods and protocols developed in CHANGE will serve as fundament for further testing and research in the field. We see CHANGE as a contribution to the strengthening of EU’s innovation capacity by providing innovative tools and methods for cultural heritage digitisation and analysis for the cultural heritage sector. A new generation of multi-skilled experts specialised in the study and monitoring of changes on cultural heritage objects in CHANGE have already taken on new tasks and challenges in the cultural heritage sector.