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The aim of this paper is to analyze the possibility to use a wide angle lens for historical basements investigation. For this purpose the test site located in the Bieliński Palace in Otwock Wielki, Poland, was chosen. In order to generate a dense point cloud Agisoft PhotoScan was used. Reconstruction results were compared both with the Terrestrial Laser Scanner point cloud and data acquired from a normal lens camera. The main advantage of the point cloud acquired by the wide angle lens is the higher robustness of camera positions in case whem thei number is limited. It should be noticed that this aspect allows to create a geometrically correct three dimensional model of an investigated object. Additionally, while a bigger area is covered by images, the distance between the camera position and the object surface can be considerably reduced. That potentially allows for tight registration of objects, typically placed in the basement area. Beside those positive features, there are also disadvantages in lens application. Usually a large range of systematic error values of image projection occur, but if properly corrected and stable, they may be neglected. Real problems appear due to the optical resolution decrease in image edge areas and existing vignetting of image illumination. Comparison between the use of both lens types has been also taken into account and presented in this paper. [ABSTRACT FROM AUTHOR]

The process of generation of geometric documentation is an important tasks in the field of conservation and management of cultural heritage objects. The 3D documentation is commonly used in conservation, restoration and analysis of historical objects and sites. The recent development of low-cost photography such as mobile phones, digital compact cameras or action cameras are now becoming dependable sources of data, which allow to create reliable and accurate documentation for different types of cultural heritage objects. The objective of this paper is to investigate the possibility of using the Xiaomi Yi 4K action camera for the documentation of frescoes through generation of orthoimages. The test field were frescoes in The Bieliński Palace in Otwock Wielki, near Warsaw (Poland), which is a great example of Late Baroque noble residence. A comparison was conducted using orthoimages from terrestrial laser scanner Z+F 5006h and the scale bars which were measured manually and were treated as reference data. This paper presents the results of the latest investigations carried out by the interdisciplinary team from three institutions: the Systems Research Institute PAS, The Department of Geodesy and Cartography of the Warsaw Technological University in association with the National Museum in Warsaw. [ABSTRACT FROM AUTHOR]

The aim of this study is to validate the possibility of using the 100 Megapixels Hasselblad Hd-6 middle format camera and Agisoft PhotoScan in the Cultural Heritage documentation. The subject of this investigations is the fresco decoration in one of the rooms in the Bieliński Palace in Otwock Wielki, near Warsaw (Poland). The frescos cover the walls of a room of 11,5 × 5,5 m in one of the wings of the palace. The results of the data analysis convincingly show that a higher resolution can be obtained using a Hasselblad which, additionally, gives better results caching the details of the documented object. This high detail of the documentation is possible to achieve when a more precise reference system is implemented and a higher resolution on image pyramid is chosen. Hence, one of the conclusions of our investigation is that a standard geodetic reference system might not be sufficient when a high detail documentation is in demand. This problem, of the choice of an appropriate reference system requires further studies. For the documentation of frescos, the use of full frame cameras and the method presented in the paper has numerous advantages. First of all it is an efficient way of documenting different aspects wall frescos, and it provides not only means for documenting, but also a basis for further analysis, that would be otherwise unavailable. All of these are in turn important factors in the investigation into the objects past and significance of historical objects. Despite the obvious drawbacks, that is the time and high-speed computers necessary to its proper application, the discussed method remains a valuable tool for scholars and curators dealing with frescoes and architecture. [ABSTRACT FROM AUTHOR]

Numerous problems related to data acquisition in urban areas occur which are not only caused by limitations of the applied equipment but also by the specific features of measurement sites. The dynamically changing environment (i.e. traffic and pedestrians, limited sight lines, temporarily occluded ground control points) causes the field measurement process more complicated and time consuming. The solution of mentioned problems can be the use of terrestrial laser scanning, which allows to acquire complete information about the measured object, as well as about its surroundings. Properly planned scanner positions allow to complete the missing data, the direct measurement of which would require much more time. One of the advantages of laser scanning is independence of measurements from the light conditions. Taking it into account it is possible to perform measurements at night in areas of heavy traffic during the day (city centres, parking lots, etc.). In this paper an attempt to automate TLS data acquisition and processing in the vector data generation process is presented. In the conclusion the advantages and disadvantages of the approach used for TLS data acquisition and processing with respect to the applicable law are discussed. [ABSTRACT FROM AUTHOR]

Terrestrial laser scanning this time became one of the most important tool which delivers reliable and rapid data, describes 3D shape and sometimes colours of analyzed objects. Robustness of this measurement approach depends on properly performed design stage in this data acquiring technology. There are many issues during data acquisition, which complicate the process. Sources of these problems are usually: reflectiveness of registered objects, angle between laser ray and a normal vector to the surface and the behaviour of the laser light on the edge of the object. Environmental limitations such as dust and fog in the air makes also difficulties with proper registrations of three-dimensional form. This paper presents research results of testing the impacts of above mentioned factors on acquisition of laser scanning data. The main tasks consisted of the following subjects: -- differentiated conception of control points displacement, -- analysis of reflection angle, intensity and its influence on point registration, -- research into accuracy of scans orientation on the base of signalized control points Results of described tasks ought to improve accuracy and especially repeatability of acquired objects surface from laser scanning technology in close range. [ABSTRACT FROM AUTHOR]

The TLS scanning technology is successfully applied in many economic sectors, which have different features and requirements. Dense clouds of points obtained as a result of TLS measurements may be considered as the optimum solution for the needs of correct and complete geometric representation of interesting objects. However, these solutions also have some disadvantages. The objective of the presented paper is to characterize factors, which influence and limit the utilization of TLS and digital images during processing of orthoimages of monumental objects, using the example of facades of the Museum of King Jan III's Palace at Wilanów. All research works were performed using the LupoScanPro software. The issue of the quality and accuracy of 3D projection of measured sites, with consideration of complexity of the object, distances and scanning angles, will be presented and discussed. Advantages and disadvantages of utilization of the DLT transformation for colouring the 3D cloud of points will be also presented. Besides, selected variants of orthoimages generation, with consideration of various density of the clouds of points, specific features of projected monumental surfaces (gilding, wallpapers) and the geometry of digital images will be reviewed. [ABSTRACT FROM AUTHOR]

The subject of this paper is a preliminary analysis of the algorithms for automatic spatial orientation of the clouds of points obtained by using a terrestrial scanner. In the proposed data processing method, the clouds of points were treated as images projected on a spherical plane of reference, additionally enriched with a depth map. The algorithms and a library of the sets of functions used in CV were presented. The implementation of a free C++ language library with algorithms used in CV was analysed. The correctness of the tie points search and operation time was examined. Clouds of points obtained from a terrestrial laser scanner Z+F 5006H were used as the source data. The analysis presented the algorithms linking the photogrammetric approach with the approach supported by CV. [ABSTRACT FROM AUTHOR]