International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B5. Istanbul 2004 
  
1. INTRODUCTION 
Arg-E-Bam can not only be considered as a former main 
economic factor but also as the symbol for the vitality of the 
region of Bam, and a means of identification for the 
inhabitants. Therefore, the authors hope for a quick and 
efficient reconstruction, maybe partly on the basis of the data 
gained through an exemplary surveying campaign performed 
in carly February 2004. Experts from UNESCO and ICHO 
(Iranian Cultural Heritage Organisation) had addressed NPR 
Co. shortly after the catastrophe. The state of damage of the 
citadel — that is most likely to be added to the World Heritage 
in danger list- had to be documented. A volume model of the 
citadel, details of cracks in the eldest walls, and an overall 
   
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Figure 1: Bam Citadel before and after the earth quake 
map of the grounds were demanded as first results as a basis 
for mapping out the procedure of cleaning the debris and 
start restoration and reconstruction works. These demands 
could be satisfied within the four days of scanning, thanks to 
the technology employed: Riegl's approach consists in a 
combination of two techniques formerly considered as 
competitive: photogrammetry, that has gained its expertise 
over the last hundred years, and the innovative laser 
scanning, developed in the last decade only. As producer of 
high-end laser scanners Riegl LMS GmbH decided to 
develop a bi-technique in order to optimise the multipurpose 
usability of scanning results and to accelerate the traditional 
photogrammetric procedure employed for this. 
  
2. METHOD 
2.1. Hardware 
The measurement system used for the Bam Citadel project 
consisted of a RIEGL LMS Z420i Laser-Scanner equipped 
with a calibrated Nikon D100 6 Mega Pixel digital camera 
mounted solidly on top of the scanner (figure 2). The 
mathematical relation between these two sensors is defined 
by a perfect hardware calibration (effectuated beforehand by 
RIEGL). In addition to the precise internal 
  
Figure 2: RIEGL LMS Z420i in Bam Citadel 
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