Caves are characterised by their great, naturally evolved geometric richness of form. Their walls are interspersed with protrusions and recesses, their passage profiles change from place to place, and dripstones and other sinter formations often determine the appearance of the cave. In the classic cave survey with measuring tape and clinometer, hardly any consideration can be given to the many details. As a rule, only a ground plan and a few characteristic sections are surveyed. Here, too, much has to be estimated on the basis of the polygon course. In surveying technology, however, there are two methods with which objects can be recorded three-dimensionally over a wide area: photogrammetry and laser scanning. These techniques can produce much more realistic and detailed images of a cave.
In a joint Bachelor's thesis at the Stuttgart University of Applied Sciences (HfT), Jonas Marquart and I used these techniques in a difficult cave environment and compared them. Our aim was to examine photogrammetry and laser scanning in terms of accuracy and cost-effectiveness and to work out the respective advantages and disadvantages.