The use of small-format and low-altitude aerial photos for the realization of high-resolution DEMs in mountainous areas : application to the Super-Sauze earthflow

Geomorphologists have to make choices and compromises, as acquisition techniques of geometrical information are numerous, depending on the specific complexity of the targeted three-dimensional objects and the requirements of the end user. This article presents the methodology and the results over a well known and documented site. This ready-to-use, low-altitude, aerial photo methodology reveals itself to be a satisfying compromise between cost, accuracy and difficulty of implementation. The selected equipment package is light enough to enable a quick reaction to unexpected events and the tools and methods are competitive with field acquisition techniques. An evaluation has demonstrated a sub-metric accuracy for the final result