الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Documentation of heritage buildings has become a key issue for most countries to preserve their old treasure buildings and being left and kept in their original shapes. Hence, it is a must and in a deep need for any country to protect these buildings through different surveying techniques for the production of a corresponding accurate three dimensional models of these buildings to ease the retrieval of their originality after being exposed to any sort of damage. So, archeological documentation of the facilities is of great importance in the process of restoration. At the beginning, photogrammetry was widely used in the field of restoration and documentation, in spite of its multiple and complicated sequential steps for data production. Over the past few years, the number of historical monuments and archaeological items recorded using innovative 3D scanning techniques has increased significantly.
In this study, the terrestrial laser scanner technique was used for heritage site documentation in two different facades in Egypt: Faculty of Engineering, Ain Shams University and El-Zaafrana palace. Actually and to reach reasonable positional accuracy, all related criteria have been investigated. Since these criteria are dependent on each other, a perfect combination must be implemented and nearly maintained when using laser scanners.
The most efficient practical condition must combine resolution, acquisition and processing time, scanned distance and field of view. The Trimble TX5 has an optimal resolution as (1/4) within a preferable range of scanned distance lying between 14.0 m and 20.0 m away from the target. The scanned distance should preserve a vertical angle in the composed field of view up to 40ᵒ. Also, it is more convenient to avoid quality greater than 4x. All these criteria is combined with suitable time in both data acquisition and processing, in order to minimize the effort and cost. These considerations have a predicted positional accuracy as 2.0 cm, with an effective 3D model.
Moreover and in order to have a complete comprehensive evaluation of the used terrestrial laser scanner, an obtained 3D model of another facade was examined. In this context, this 3D model revealed a good matching of all existing details and decorations. Also, the dimensions and orientations of some features were extracted with high accuracy.