Repeat Photography and Virtual Reconstruction of Los Santos de Ángeles de Guevavi, Tumacácori National Historical Park, Arizona

ABSTRACT Since its abandonment in 1775, the mission Los Santos Ángeles de Guevavi has undergone severe erosion and loss, rendering the eighteenth-century adobe church and associated mission structures difficult for the visiting public to understand and appreciate. This research examines the use of repeat photography and virtual reconstruction of Guevavi Mission to visualise and quantify deterioration of the church while also improving visitor understanding of the site. Repeat photography processed through JuxtaposeJS provides an interactive mode of viewing changes over time, while 3D modelling creates a digital reconstruction of the complex during its occupation. Both methods taken together also provide a semi-quantitative means of documenting material loss of the Guevavi Mission church over time and monitoring loss and the efficacy of current and future preservation methods.