Photogrammetric surface modeling can provide a useful means of rapidly mapping the topography of steep or vertical faces from a safe distance. The example below shows the problem – a vertical cliff with a dangerous, heavily vegetated upper slope. It would
not be possible to acquire accurate levels for this part of the site, however accurate topographic information is vital for the design of the site development.

Plate 1: View of problem (with PI-3000 control points)

Plate 2: Final photogrammetry land surface exported as xyz and displayed as colour
contours.

Original site plan overlain showing assumed levels as black contours completely missing the vertical face.

Plate 3: Screen shot from Imagemaster showing model surface of cliff and digital surface model contours

CASE STUDY: BOUNDARY SURVEY IN ALASKA USING IMAGEMASTER

For larger surveys where greater altitudes are required, we can use aerial photography from helicopters or planes and even satellite images. We recently carried out some training for an Imagemaster Pro customer in Alaska. The aim of this work was to map surface topography and plot boundaries in a remote settlement. This project has been published and can be viewed in more detail here.