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Although multispectral imaging (MSI) of cultural heritage, such as manuscripts, documents and artwork, is becoming more popular, a variety of approaches are taken and methods are often inconsistently documented. Furthermore, no overview of the process of MSI capture and analysis with current technology has previously been published. This research was undertaken to determine current best practice in the deployment of MSI, highlighting areas that need further research, whilst providing recommendations regarding approach and documentation. An Action Research methodology was used to characterise the current pipeline, including: literature review; unstructured interviews and discussion of results with practitioners; and reflective practice whilst undertaking MSI analysis. The pipeline and recommendations from this research will improve project management by increasing clarity of published outcomes, the reusability of data, and encouraging a more open discussion of process and application within the MSI community. The importance of thorough documentation is emphasised, which will encourage sharing of best practice and results, improving community deployment of the technique. The findings encourage efficient use and reporting of MSI, aiding access to historical analysis. We hope this research will be useful to digitisation professionals, curators and conservators, allowing them to compare and contrast current practices.

Historical data sources are used by a wide variety of disciplines, but rarely do they look outside their particular research fields at how others are using and applying historical data. The use and application of historical data has grown rapidly over the last couple of decades within the meteorological, geophysical and hydrological disciplines, but have done so relatively independently. By coevolving, each discipline has developed separate themes or areas, with varying degrees of uptake beyond their academic communities. We find that whilst the geophysical discipline has been relatively successful in engaging with international policymakers and stakeholders, this has not been reflected within the meteorological or hydrological disciplines to date. This disparity has occurred for a variety of reasons, including varying scales of disaster and social, political and cultural structures. In examining current developments within the disciplines, evidence suggests that this disparity is lessening, as each are using online databases and some citizen science, but that they continue to evolve independently with little unifying structure or purpose. This continued autonomy makes multi-hazard analysis challenging which, considering the potential that historical datasets present in the emerging field of multi-hazards analysis, is a considerable hindrance to this field of research. In looking forward, opportunities emerge for improved understanding of the risks presented to societies by natural hazards in the past, but also for examining how resilience, behaviour and adaptation alter during periods of repose.

Multispectral (MSI) imaging of historical documents can recover lost features, such as text or drawings. This technique involves capturing multiple images of a document illuminated using different wavelengths of light. The images created must be registered in order to ensure optimal results are produced from any subsequent image processing techniques. However, the images may be misaligned due to the presence of optical elements such as filters, or because they were acquired at different times or because the images were captured from different copies of the documents . There is little prior work or information available about which image registration techniques are most appropriate. Image registration of multispectral images is challenging as the illumination changes for each image and the features visible in images captured at different wavelengths may not appear consistently throughout the image sequence. Here, we compare three image registration techniques: two based on similarity measures and a method based on phase correlation. These methods are characterized by applying them to realistic surrogate images and then assessed on three different sets of real multispectral images. Mutual information is recommended as a measure for affine image registration when working with multispectral images of documentary material as it was proven to be more robust than the other techniques tested.