FROM DAGUERREOTYPES TO DIGITAL AUTOMATIC PHOTOGRAMMETRY. APPLICATIONS AND LIMITS FOR THE BUILT HERITAGE PROJECT

This paper will describe the evolutionary stages that shaped and built, over the time, a robust and solid relationship between ‘indirect survey methods’ and knowledge of the ‘architectural matter’, aiming at producing a conservation project for the built heritage. Collecting architectural data by simply drawing them was considered to be inadequate by John Ruskin already in 1845. He strongly felt the need to fix them through that ‘blessed’ invention that was the ‘daguerreotype’. Today taking simple photographs is not enough: it is crucial to develop systems able to provide the best graphics supports (possibly in the third dimension) for the development and editing of the architectural project. This paper will focus not only on the re-examination of historical data, on the research and representation of the ‘sign’, but also on the evolution of technologies and ‘reading methods’, in order to highlight their strengths and weaknesses in the real practice of conservation project and in the use of the architectures of the past

Validation of Cartosat-1 DTM generation for the Salon de Provence test site

Cartosat-1 is the eleventh satellite of the Indian Space Research Organisation series and is primarily meant for topographic mapping and Digital Terrain Model (DTM) generation. In the framework of the Cartosat-1 Scientific Assessment Programme, the Politecnico di Milano University (Italy) evaluated as Co-Investigator the performances of the Cartosat-1 satellite in the generation of DTMs. This paper describes the outcomes for the Salon de Provence test site (France) with respect to existing standards and products actually used in France and also provides a comparison with the global Shuttle Radar Topography Mission’s DTM supplied by NASA and widely used in the remote sensing community

From point cloud to BIM: a modelling challange in the Cultural Heritage field

Speaking about modelling the Cultural Heritage, nowadays it is no longer enough to build the mute model of a monument, but it has to contain plenty of information inside it, especially when we refer to existing construction. For this reason, the aim of the research is to insert an historical building inside a BIM process, proposing in this way a working method that can build a reality based model and preserve the unicity of the elements. The question is: "What is the more useful mean in term of survey data management, level of detail, information and time savings?" To test the potentialities and the limits of this process we employed the most used software in the international market, taking as example some composed elements, made by regular and complex, but also modular parts. Once a final model is obtained, it is necessary to provide a test phase on the interoperability between the used software modules, in order to give a general picture of the state of art and to contribute to further studies on this subject

EMERGENCY SURVEY OF REMOTE AND ENDANGERED ARCHAEOLOGICAL SITES

The paper describes the survey activities of the late Roman archaeological site of Umm al-Dabadib (Egypt). The interesting casestudy can be taken as an example in case of emergency surveys, as this method allows the complete 3D acquisition of a vast and complex area in a very short time and with the aid of simple instruments

3D visualization and virtual reality for cultural heritage diagnostic

In the past years, many different new technologies for Cultural Heritage Diagnostic have been developed. In particular laser scanner surveys with digital photogrammetry and also multi-spectral surveys are becoming very useful and inalienable tools for non invasive diagnosis. In the SIDART Project (Integrated System for Cultural Heritage diagnosis), we develop a software able to visualize and elaborate triangulated surfaces coming from high resolution laser scanner survey. In this paper, we want to present the most innovative aspect of our study, that is the possibility to visualize and work in default mode or in immersive Stereoscopy (3D mode). This lets the operator perceive the third dimension and the “virtual investigation” of the object becomes more realistic. This lets us take into consideration in a more simple, natural and correct way and also reduce the possibility to make wrong evaluation due to the false prospective of the classic visualization

Underwater calibration of dome port pressure housings.

Underwater photogrammetry using consumer grade photographic equipment can be feasible for different applications, e.g. archaeology, biology, industrial inspections, etc. The use of a camera underwater can be very different from its terrestrial use due to the optical phenomena involved. The presence of the water and camera pressure housing in front of the camera act as additional optical elements. Spherical dome ports are difficult to manufacture and consequently expensive but at the same time they are the most useful for underwater photogrammetry as they keep the main geometric characteristics of the lens unchanged. Nevertheless, the manufacturing and alignment of dome port pressure housing components can be the source of unexpected changes of radial and decentering distortion, source of systematic errors that can influence the final 3D measurements. The paper provides a brief introduction of underwater optical phenomena involved in underwater photography, then presents the main differences between flat and dome ports to finally discuss the effect of manufacturing on 3D measurements in two case studies

Geometric and Optic Characterization of a Hemispherical Dome Port for Underwater Photogrammetry

The popularity of automatic photogrammetric techniques has promoted many experiments in underwater scenarios leading to quite impressive visual results, even by non-experts. Despite these achievements, a deep understanding of camera and lens behaviors as well as optical phenomena involved in underwater operations is fundamental to better plan field campaigns and anticipate the achievable results. The paper presents a geometric investigation of a consumer grade underwater camera housing, manufactured by NiMAR and equipped with a 7'' dome port. After a review of flat and dome ports, the work analyzes, using simulations and real experiments, the main optical phenomena involved when operating a camera underwater. Specific aspects which deal with photogrammetric acquisitions are considered with some tests in laboratory and in a swimming pool. Results and considerations are shown and commented

Sharing high-resolution models and information on web: The web module of bim3dsg system

BIM3DSG system is described here. It is an ad hoc designed BIM system created for Cultural Heritage applications. It proposes some solutions to solve some issues related to the use of BIM in this field. First, it tries to resolve the problem of managing huge, complex, high resolution and heterogeneous 3D models, and then it offers a practical, easy and efficient solution for a wide sharing of data and information

INTEGRATION OF 3D MODELS AND DIAGNOSTIC ANALYSES THROUGH A CONSERVATION-ORIENTED INFORMATION SYSTEM

In the recent years, mature technologies for producing high quality virtual 3D replicas of Cultural Heritage (CH) artefacts has grown thanks to the progress of Information Technologies (IT) tools. These methods are an efficient way to present digital models that can be used with several scopes: heritage managing, support to conservation, virtual restoration, reconstruction and colouring, art cataloguing and visual communication. The work presented is an emblematic case of study oriented to the preventive conservation through monitoring activities, using different acquisition methods and instruments. It was developed inside a project founded by Lombardy Region, Italy, called “Smart Culture”, which was aimed to realise a platform that gave the users the possibility to easily access to the CH artefacts, using as an example a very famous statue. The final product is a 3D reality-based model that contains a lot of information inside it, and that can be consulted through a common web browser. In the end, it was possible to define the general strategies oriented to the maintenance and the valorisation of CH artefacts, which, in this specific case, must consider the integration of different techniques and competencies, to obtain a complete, accurate and continuative monitoring of the statue

LEARNING GEOMATICS FOR RESTORATION: ICOMOS SUMMER SCHOOL IN OSSOLA VALLEY

Documentation and preservation of widespread rural heritage are today possible only if you can activate processes of conservation headed by local communities, thereby recognizing the link between the communities and their culture. The cultural heritage places (villages, sites and landscapes) can take different values; action is needed respecting the right of communities to identify the values contained in them. ‘Collaborative networks should be set up at different levels among multiple stakeholders in order to address issues related to heritage and create new value chains through innovative synergies. Dynamic, flexible, inclusive and integrated processes of engagement need to be employed for assessing long-term social impacts of heritage conservation programmes’ (Icomos, 2014). In 2011 the 3DSurvey Group of the Politecnico di Milano in collaboration with the Canova Association initiated an annual summer school program entitled ‘Laboratory of Places 2017, Ghesc and surroundings, History, survey, evolution Laboratory of Places'. The definition of “Laboratory of Places 2017, Ghesc and surroundings” links the idea of an inhabited space to an open space suitable for study, research, and an interactive absorption and confrontation of differing ideas. Founding elements of the project involve educational collaborations with university, but equally important will be the development of programs with local schools, associations, and public administration (Quaderni di Ghesc, 2010)