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tumacacori Survey Methodology

Ortho-rectified Photodocumentation
In January 2015, the Architectural Conservation Laboratory conducted a site visit in order to conduct preliminary investigations to aid in subsequent analyses and assessment. During this trip, high-resolution photographs of the façade were taken in order to create an ortho-rectified photomontage as a base image for future inspection. This was done by using a DSLR camera to photograph portions of the façade’s surface to then digitally stitch the images to fit previous photogrammetric measurements as recorded during the Historic American Buildings Survey conducted in 1975 by Perry, Myra, and Christina Borchers at Ohio State University.
In addition to preliminary documentation, original surface finishes and subsequent repair campaigns were analyzed in-situ and small samples were taken for further laboratory analysis. Historic images informed sampling strategy and all sample locations were carefully photographed and notated. Samples of finish coatings were also taken from previously fallen fragments that had been collected by NPS staff.

montage
Above: The completed rectified montage.
surveying
Using high-resolution photography to create an ortho-rectified photomontage.
sampling
Taking small samples of repair campaigns for further analysis
comparison
Right: Working from the historic watercolor rendering helps  inform decisions about where to sample.