The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B7. Beijing 2008 
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Figure 9. 3D city model of Istanbul Historic Peninsula as LoDl 
6.2 3D city model in level of detail 2 (LoD2) 
Currently, the modelling group is producing a 3D city model in 
LoD2 (Fig. 10) by combining the block model with the roofs, 
which are measured as 3D polylines by the roof mapping group. 
Therefore, the measured polylines of the roofs will be converted 
to 3D planes and thereafter the roof comers can be connected 
perpendicularly to the corresponding roof points of the block 
model. In this modelling process the building heights of each 
block model will be matched with the height of the measured 
roof. It was quickly realised that there were some discrepancies 
between the block model and the roof model, i.e. the vector data 
from cadastre did not fit very well with the 
photogrammetrically determined roofs. Therefore, it was 
decided to change the method of production by using measured 
height points on the ground to generate the facades, i.e. the roof 
comers can be connected perpendicularly to the measured 
ground points. 
Currently, the Suleymaniye region could be almost finished as 
LoD2 product as illustrated in Fig. 10. 
Figure 10. 3D city model of Istanbul Historic Peninsula as 
LoD2 in the Suleymaniye area superimposed on an orthophoto 
as an overview (top) and detailed view (bottom) 
6.3 3D city model in level of detail 3 (LoD3) 
The LoD3 is a high quality product, which is generated from 
the detailed roof-mapping and from building facades including 
photo-realistic texture mapping of the each building. Similar 
detailed models of north German castles were generated by 
digital photogrammetry (Kersten et al., 2004) or archaeological 
3D objects in the Republic of Yemen by a combination of 
photogrammetry and terrestrial laser scanning (Kersten, 2007). 
Due to the very time-consuming generation of such products 
only one project part, as pilot project, has been completed thus 
far. For an architectural comparison of an existing and planned 
situation two 3D models (old/new) of the same block (511) in 
Suleymaniye Bôlgesi were generated. The modelling of the 
planned situation was based on 2D drawings, while the existing 
situation could be modelled using the facade drawing data, 
which was generated from laser scanning data. For the existing 
buildings photo realistic textures were available, while for the 
planned situation textures from the library of ArchiCAD were 
used. Following a request from the project architects a video 
sequence (4:47min, 640 x 480 pixel, 46 MB as wmv format) 
was generated for a visual comparison of the existing and the 
planned situation of a block in Suleymaniye Bôlgesi. 
6.4 3D modelling of landmarks 
The 3D modelling group generated photo-realistic 3D models 
of landmarks, such as the “German Fountain” shown in figure 
11, with data from façade mapping using 3ds max. Additionally, 
the group was able to perform 3D modelling using existing 
ground and façade plans from different sources (e.g. Sultan 
Ahmet Mosque, see Fig. 12). The details and the precision of 
these models are more than sufficient for visualisation purposes. 
Finally, video sequences can be generated from any modelled 
object using 3ds max. 
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