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support the operator during the orientation process are still 
under development. 
2.5 Differential Rectification 
The DSM and the oriented image data are combined and digital 
orthoimages are created in a short period of time. We used a 
digital consumer camera (Nikon Coolpix 4300). Because of the 
significant distortion of the optics, it was necessary to consider 
them in the orientation and rectification. The distortion model 
described in Luhmann (2000) has been used. 
Figure 4. Orthoimage 
If the results are insufficient, for example because of 
inaccessibility of some parts of the object, there are techniques 
to solve any ambiguities by using digital photogrammetry based 
Figure 5: Drawings derived from the Orthoimages and some 
additional geodetic information. 
on the acquired and oriented images at any time after the 
campaign. 
In the result the balconies are located at the correct location. 
Above them are some occluded areas, which have been colored 
in gray in the orthoimage. If additional image from a better 
point of view are available this gaps in the orthoimages can be 
closed during the mosaiking process. The roof has been 
removed. The image of the roof is not suited for this purpose, 
because of the inappropriate aspect. 
3. DRAWINGS 
Based on this orthoimages line drawings of the object have been 
derived. This has been performed by monoplotting on the 
orthoimage. A small part is shown n Fig. 5. The heights of the 
roof and the chimneys have been added based on geodetic 
measurements. 
4. MOSAIKING 
Digital orthoimages or rectified images can be combined to 
mosaics. The example for this is a parametric rectification of 
three digital images (Fig. 6). The exposure time was selected 
automatically, so that the images show very different brightness 
and contrast. After a parametric rectification (Fig. 7), using 
Archimedes3D Basic the three rectified images are mosaiked 
geometrically (Fig. 8). The differences in brightness and 
contrast are clearly visible. To avoid this a radiometric 
mosaiking tool, based on the approaches for satellite image data 
(Kahler 1989) has been adapted for architectural images. The 
concept is an equalisation of the sum histograms. The result of 
this fully automatic process is shown in figure 9. 
5. CONCLUSIONS 
Using this package, a total station and a digital camera become 
a high quality documentation system providing detailed data for 
the generation of real orthoimages and other requested products 
in heritage documentation. 
6. REFERENCES 
Juretzko, M., 2002: The System TOTAL for Recording the 
Geometry and Image Data of Historic Buildings and 
Monuments. Proc. of the XVIII. CIPA Int. Symposium, 
Potsdam, Germany, Oct. 18.-21 2001. International Archives 
for Photogrammetry and Remote Sensing (IAPRS). Vol. 
XXXIV-5/C7, pp. 611-613. 
Kahler, M., 1989: Radiometrischen Bildverarbeitung bei der 
Herstellung von Satelliten-Bildkarten. Deutsche Geoatische 
Kommision DGK, Reihe C 348. 
Luhmann, T., 2000: Nahbereichsphotogrammetrie. Wichmann, 
Karlsruhe. 
Wehr, Aloys & Albert Wiedemann (1999): Fusion of Photo- 
grammetric and Laser Scanner Data Proc. of the CIPA Int. 
Symposium '99, Int. Archives for Photogrammetry and Remote 
Sensing, Vol. XXXIV, Part 5C1B, Olinda, Brazil, 3.-6. Okt. 
1999, published on CD & on http://www.fpk.tu- 
berlin.de/~albert/litlis.html 
Wiedemann, A. (1996): Generation of Digital Orthoimages 
Using Digital Surface Models. International Archives for