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Fräs 
the left part of a page, an index is shown that gives the structured information on documentation. Clicking through index, one comes 
to different levels and gets the view into documentation. 
Figure 2: First page of the presentation 
The structure that was developed from many years of our experience in producing technical documentation of monuments and sites 
in Slovenia, will be described on an example of a real project - the Dome of Ljubljana, financed by Restoration Centre of Slovenia. 
The dome or the cathedral of St. Nikolaj is an important Slovenian baroque church. The central market in Ljubljana takes place in the 
vicinity of the church, which is surrounded with other buildings as well. The disposition for photogrammetric survey is difficult and a 
lot of traffic is all the time around the church. Thus, field measurement were accomplished during weekends and nights. 
Very detailed technical documentation was produced for the church in different phases taking all together three years. In the first 
year, a 3D model of the exterior, maps of all facades and vertical and horizontal cross sections were produced. In the second year, the 
documentation was extended with 3D model of the interior, maps of interior walls (with main elements) and orthophotos of some 
frescoes. In the third year, very detailed structures and even furniture were drawn in the maps of interior. Such approach “from large 
to small” enable to combine different types of technical documentation with different level of detail and different accuracy. Our 
experience shows that it is not always good to produce very detailed 3D model for many reasons. First, it is time and cost consuming 
and the amount of data increase significantly with the details on a model. Capacities of an usual PC becomes quickly too small for 
working with the model. On the other hand, the conservators are still more familiar to work with vector maps. Thus, our approach 
and advice is to produce first a 3D model of a building that have the main architectonic features, but the measures of significant 
dimensions are accurate enough (mostly adequate to the accuracy of graphical scale in 1 : 50). Than, a projection of a facade is 
produced from the model and details are measured and added to the map. The same hierarchy could go down to the smallest details 
of the objects and even furniture could be integrated. It is good to produce a 3D model first in order to assure the topological 
consistency of data - this is difficult to assure and control with separate 2D maps (e.g. measures on facades and cross sections should 
be consistent). 
The structure of data is presented in the index on left (Figure 3). The first level of hierarchy are the following categories of 
documentation: 
• technical report 
• vector maps 
• raster maps 
• 3D models 
• photo archive