International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B3. Istanbul 2004 
  
  
same direction. Correspondingly, biases were 6-8 cm and 
standard deviations +4-6 em for the flight strips to the opposite 
directions. To summarize, the planimetric accuracy is worse 
than vertical but acceptable for various purposes. 
The first pulse mode observations tend to exaggerate the area 
and the lengths of the roofs. The first pulse data give about 11- 
14 % larger building roofs than the last pulse data. Lengths of 
the roofs were about 21 cm longer from the first pulse data than 
in reality. Correspondingly, the last pulse mode gives 
underestimated results. Lengths were about 25 cm smaller than 
the obtained reference measurements. These systematic effects 
have to be realized e.g. in cartographic applications. 
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