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light, which, in practice, proves to be quite a contradiction on an 
external site. For texture mapping to be possible at post 
processing stage, the digital photos must be taken from exactly 
the same position as the laser scan. Thus, if one wishes to use 
the integrated camera for texture mapping the laser scanner 
cannot be shifted till daytime otherwise the texture mapping 
cannot be automatic. 
Unless Thealasermetry is used, the alternative would be to add 
3-dimensional targets with an identifiable point (eg. pyramids). 
This would add even more targets to the other targets (cross 
hairs & spheres) but would enable the laser scanning and the 
digital photography to take place at different times provided the 
targets are left in place. 
3.7 Using Laser Scan data to complement digital photgram- 
metry techniques 
The MCR’s field and lab trials thus confirmed a number of 
problems that the two technologies posed and suggested some 
methods of using one technology to complement the other. In 
summary: 
i. Digital photogrammetry is more accurate in outline rendi 
tion and, subject to reference measurement control using a 
theodolite on a large site, is capable of providing a frame 
work where metric error popagation is reduced to a mini 
mum;