Multimethod digitalisation of a large-format school map from the first half of the 20th century

Purpose This study aims to delve into the effectiveness of applying traditional and more advanced digital means to document elements of cultural heritage, in this case large-format cartography. Application of multimethod digitalisation to a school map of the American continent dating to the early part of the 20th century has served to address specific issues, notably its multilayers consisting of paper, inks and a protective varnish on a textile medium. Its large format is likewise an obstacle to its digital capture. Design/methodology/approach The method applied here resorted to three registration systems: single-shot photography, panoramic photography and photogrammetry. The first two widely serve to capture works of large-format, whereas the third is commonly used to record volumetric assets. A variety of parameters were applied, notably different focal lengths, capture methods and processing software. The images obtained in each case were subjected to qualitative and quantitative comparisons so as to analyse their differences in terms of resolution and accuracy when compared to the map's real measurements, key criteria when duplicating cartographic documents. Findings Although the final products gleaned from the digital photographs, panoramic photographs and photogrammetry fulfil the basic functions required to record documents housed in archives, libraries, museums and other cultural institutions, this study highlights new advances and complementary functions stemming from certain of these techniques. Originality/value Digitalisation is a tool that serves to register, preserve, disseminate and analyse cultural heritage. However, some of the available techniques have rarely been applied specifically to graphic and documentary artefacts. It is for this reason that this study intends to demonstrate their utility in the detailed study of this heritage typology. Moreover, optimising the school map into a digital form favours its dissemination and remote consultation while simultaneously minimising direct manipulation, hence improving its long-term preservation.