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Photogrammetric Recording

The object to be recorded has a surface of about 6.3 square meters. It couldn't be moved and the working space around is very limited. Light conditions must be accepted as found on site. Photos were taken for stereo photogrammetry and multi image photogrammetry as well as details. Artificial targets are used as ground control points. Co-ordinate measurements were taken from two different positions with a Topcon Image Station.

The stereo photogrammetry was carried out like an aerial flight. For taking vertical images a bar of approx 3.5 meter length was built from metal pieces and moved crossways. The Canon Powershot G10 camera moved lengthways (flight direction) in stripes with approx. 60% overlapping over the model. Shutter release was provided by a remote control unit. Image resolution is 4416 x 3312 pixel with a pixel size of about 1.7 microns. The focal length setting was 6.1 mm hyperfocal. Due to the long exposure time and the small pixel size the images display some noise. The flight simulation delivered total 32 images in four stripes with

In addition an image bundle for multi image photogrammetry was taken but not used for later evaluations. Structure from motion image based modeling was tested in a small area. But could not compete against the stereoscopic photo arrangement.

Vertical photo

Vertical photo for parallax measurement

Oblique photo

Image for multi image evaluation

Detailed photograph

Detailed photograph

Total station measurement Canon powershot G10 Canon powershot G10

Principle of exposure arrangement

© University of Applied Sciences Bielefeld 2011