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A.20 Front (top and bottom left) and back (top and bottom right) views (150 mm FOV) of the 3D digital surface model with visible overlapping grooves. Detail of strokes overlapping (bottom) – the models are reoriented for higher readability. The following approach is based on the 2D profile surface texture standard ISO 25178-2:2012, using the 3D digital surface model captured in 2012 with the 90 mm FOV.
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Moitinho de Almeida, V. (2013). "Towards Functional Analysis of Archaeological Objects through Reverse Engineering Processes". Ph.D. Thesis. Barcelona: Universitat Autònoma de Barcelona (UAB). http://hdl.handle.net/10803/129161
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... However, during the last 20 years, studies have started to shift from observational methods (Moro Abadía and González Morales, 2020) and the search for the meaning of an "image" (Tomášková, 2020) to deciphering the production processes involved in the original creation of the archeological findings, their material and organizational structures (Dobres, 2001(Dobres, , 2010Moro Abadía and González Morales, 2020;Tomášková, 2020). New documentation methods were harnessed to follow this tendency (Bourdier et al., 2017;Díaz-Andreu et al., 2006;Díaz-Guardamino and Wheatley, 2013;Domingo et al., 2013;Fritz and Tosello, 2007;Fritz et al., 2016;Intxaurbe et al., 2020;Medina-Alcaide et al., 2018;Rivero et al., 2019;Robin, 2015;Trinks et al., 2005) and specifically for dealing with engraving and incised surfaces (e.g., Bello and Soligo, 2008;Bello et al., 2013;d'Errico, 1992;d'Errico and Backwell, 2016;d'Errico and Cacho, 1994;d'Errico and Villa, 1997;d'Errico et al., 2020;Fritz, 1999;Fritz and Tosello, 2007;Moitinho de Almeida, 2013;White, 2006White, , 2007. ...
Ancient rock engravings evoke the interest of archeologists and art historians as an important remnant of human cultures. Traditionally, engraved images are studied based on iconography, iconology, and stylistic characteristics, with little emphasis on execution technology. In contrast, the research method presented in this study strives to characterize the techniques adopted for making rock engravings in ancient times, with technological variations considered as indicators of the engraver’s production process. 3-D scans of two ancient engravings and contemporary graffiti were obtained from Site 25 in Timna Park, Southern Israel. The models were analyzed with ArchCUT3-D, a software specifically developed to precisely evaluate the 3-D micromorphological characteristics of the incisions making up the engraving. The software analyzes the surface micromorphology by extracting 3-D slices of the incisions using an accurate and repeatable method. Our results indicate that different incisions were executed by remarkably distinct techniques of stroking the rock surface with a sharp tool. The identification of discriminant characteristics enabled us to demonstrate the particularities of the engraving operations, such as ergonomic conditions and the level of consistency of the engraving gesture. ArchCUT3-D thus provides a computational method for incision technique recognition through micromorphology specifications, and the reconstruction of engraving gestures and individual production procedures.
... The digital models were processed and analysed with "Rapidform XO Scan 2010". The 3D model acquisition followed established protocols (López-Bultó, 2015;Moitinho, 2013) regarding the preparation of the materials and the workplace, digital data acquisition, digital data processing and digital model generation. The application of these protocols helped in solving the difficulties that structured-light scanners present with regard to dark and wet materials. ...
Woodworking technology in prehistory has been studied primarily indirectly, which could be partial and incomplete information on wood technology. The Neolithic site of La Draga (Banyoles, Spain), due to its preservation of organic archaeological materials, presents exceptional conditions for its study. This paper will focus on the manufacture process of an ensemble of 44 wooden digging sticks from the site. It has been developed an experimental analysis, followed by the tool mark analysis of 3D models which suggests a differential woodworking process depending on the wooden raw material used; boxwood digging sticks required much more complex woodworking techniques. The 3D digitalization and tool mark analysis has been an excellent solution in order to prevent the fragile archaeological wooden tools from degradation and also it opens a wide and new range of possible research lines to be developed in the upcoming years as signature analysis.
... The tip of one end has a small fracture while the other is slightly crushed, as can be seen from the disintegrated fiber at the tip. The bow displays a section between convex and plano-convex and a curved profile, of which the dorsal side is convex and the ventral is concave (López 2015;Moitinho de Almeida 2013;Piqué et al. 2015). ...
... • Consultation with cultural heritage professionals has confirmed the relevance of 3D imaging and established that, by creating accurate geometric representations, user motivations can be addressed for surface measurement and inspection, deformation monitoring, and 3D printing with particular benefits for conservation and research, [29,30]. ...
... deviation on the coin's surface morphology, 3D surface area and volume measurements, cross-sections), to their quantitative characterization and analysis. Although a 3D digital model does not provide a complete picture of the object, it should be understood as a powerful tool-potentially, with valid data-for visualisation and cultural heritage research, and complementary to other measurement methods [29]. Overall, the analytical methods used in this case study contributed to a holistic knowledge of the coins at different scales and with different types of information. ...
This case study is applying imaging and analytical techniques from multiple scientific disciplines to digitise coins and evaluate 3D multi-modal visualisation. Two ancient Roman silver denarii were selected as test objects to establish whether the proposed digital recording methods can support professional numismatic comparison of features and properties. The coins raise questions concerning their provenance, authenticity, design, purpose of issue and historic usage, but they also pose considerable recording challenges due to their material and surface properties, which are the main focus in this paper. The coins have been examined by the following techniques: dome photography for image sets for PTM/RTI visualisation and photometric stereo; X-ray microtomography for detection of cracks or impurities; Scanning Electron Microscopy for detailed surface investigation; Energy-Dispersive X-ray Spectroscopy for elemental analysis; micro X-ray fluorescence spectrometry mapping; 3D laser and structured light scanning for 3D spatial capture; photogrammetry/structure from motion, focus-stacking. The results indicate the feasibility of such techniques for museum documentation and as contribution to scientific examination of coins in general.[Figure not available: see fulltext.]
... Although a 3D digital model does not provide a complete representation of the object, it should be understood as a highly powerful tool-potentially, with valid data-for cultural heritage research, and complementary to other measurement techniques (as used in this case study) and fields of knowledge (Moitinho de Almeida 2013). ...
In this unique collection the authors present a wide range of interdisciplinary methods to study, document, and conserve material cultural heritage. The methods used serve as exemplars of best practice with a wide variety of cultural heritage objects having been recorded, examined, and visualised. The objects range in date, scale, materials, and state of preservation and so pose different research questions and challenges for digitization, conservation, and ontological representation of knowledge. Heritage science and specialist digital technologies are presented in a way approachable to non-scientists, while a separate technical section provides details of methods and techniques, alongside examples of notable applications of spatial and spectral documentation of material cultural heritage, with selected literature and identification of future research. This book is an outcome of interdisciplinary research and debates conducted by the participants of the COST Action TD1201, Colour and Space in Cultural Heritage, 2012–16 and is an Open Access publication available under a CC BY-NC-ND licence.
... As a rule, one may say that the more information about an artefact and its context is available the more valuable it is for archaeological research (Jones 2003;Eggert 2013). However, more than data quantity it is data quality and adequacy that is needed (Moitinho de Almeida 2013). ...
... Additionally, a good 3D measuring instrument for a coin will be both precise and accurate by acquiring the same 3D coordinates of the coin each time (repeatability, e.g., measurement results: diameter of coin is either 2.819 cm or 2.82 cm each time) and each time they are close to the real coin (e.g., diameter of real coin is 2.8 cm)-within this type of study, the measurement uncertainty may be negligible. All in all, depending on the scientific question prompting the research agenda and the scale of analysis required, among other factors, the accuracy, resolution, precision, and uncertainties of the measurements should be high enough to fulfil the project's or expert's needs for improved scientific documentation and study of the cultural heritage object (Moitinho de Almeida 2013). ...
In this unique collection the authors present a wide range of interdisciplinary methods to study, document, and conserve material cultural heritage. The methods used serve as exemplars of best practice with a wide variety of cultural heritage objects having been recorded, examined, and visualised. The objects range in date, scale, materials, and state of preservation and so pose different research questions and challenges for digitization, conservation, and ontological representation of knowledge. Heritage science and specialist digital technologies are presented in a way approachable to non-scientists, while a separate technical section provides details of methods and techniques, alongside examples of notable applications of spatial and spectral documentation of material cultural heritage, with selected literature and identification of future research. This book is an outcome of interdisciplinary research and debates conducted by the participants of the COST Action TD1201, Colour and Space in Cultural Heritage, 2012–16 and is an Open Access publication available under a CC BY-NC-ND licence.
... Paralelamente a dichas aplicaciones, un número creciente de proyectos arqueológicos fundamentan sus investigaciones en el análisis de modelos digitales 3D generados con sistemas ópticos de medición de corto alcance. Entre éstos pueden citarse estudios cuantitativos que abordan distintos aspectos de la tecnología lítica, por ejemplo aquellos dedicados al retoque, la dinámica de reducción y la predicción de masa o del volumen originales de los artefactos (Clarkson y Hiscock, 2011;Lin et al., 2010;Morales et al., 2015;Muller y Clarkson, 2014), así como la caracterización y variabilidad morfológicas (Bretzke y Conard, 2012;Li et al., 2016;Moitinho de Almeida, 2013, Moitinho de Almeida et al., 2013aShipton y Clarkson, 2015) (figura 1). ...
... As a rule, one may say that the more information about an artefact and its context is available the more valuable it is for archaeological research (Jones 2003;Eggert 2013). However, more than data quantity it is data quality and adequacy that is needed (Moitinho de Almeida 2013). ...
... To follow AAT (IDs: 300387703 and 300389893), "digital reconstruction"-also referred to as "virtual reconstruction"-is a specific branch of reconstruction, in the sense that it makes use of computers and appropriate programming language or software to construct digitally, or "fill in the losses and lacunae" of missing digital data, including those of digital representations of cultural heritage objects. Physical (i.e., real world) and digital reconstructions (e.g., experimental archaeology and computer simulation methods and techniques) have already demonstrated their usefulness in helping to gain practical knowledge and in testing theoretical hypotheses (Ingersoll et al. 1977;Skibo 1992;Terradas and Clemente 2001;Hopkins 2008;Moitinho de Almeida 2013;Moitinho de Almeida et al. 2013;PfarrHarfst and Wefers 2016). ...
... Additionally, a good 3D measuring instrument for a coin will be both precise and accurate by acquiring the same 3D coordinates of the coin each time (repeatability, e.g., measurement results: diameter of coin is either 2.819 cm or 2.82 cm each time) and each time they are close to the real coin (e.g., diameter of real coin is 2.8 cm)-within this type of study, the measurement uncertainty may be negligible. All in all, depending on the scientific question prompting the research agenda and the scale of analysis required, among other factors, the accuracy, resolution, precision, and uncertainties of the measurements should be high enough to fulfil the project's or expert's needs for improved scientific documentation and study of the cultural heritage object (Moitinho de Almeida 2013). ...
The essays in this collection are transformative, moving beyond basic collaboration and skilfully contextualizing both scientic knowledge in the humanities and humanities knowledge in the sciences. Doing so not only heightens the quality of the research, but heightens understanding, redrawing traditional lines between disciplines and redening what it means to truly collaborate and to be a scholar in the digital age."-Bill Endres, University of Oklahoma In this unique collection the authors present a wide range of interdisciplinary methods to study, document, and conserve material cultural heritage. The methods used serve as exemplars of best practice with a wide variety of cultural heritage objects having been recorded, examined, and visualised. The objects range in date, scale, materials, and state of preservation and so pose dierent research questions and challenges for digitization, conservation, and ontological representation of knowledge. Heritage science and specialist digital technologies are presented in a way approachable by non-scientists, while a separate technical section provides details of methods and techniques, alongside examples of notable applications of spatial and spectral documentation of material cultural heritage, with selected literature and identication of future research.
... Research with cultural heritage professionals has confirmed the relevance of 3-D imaging and established that, by creating accurate geometric representations, user motivations can be addressed for surface measurement and inspection, deformation monitoring, and 3-D printing. 21,22 Cross-sections, surface heights, and profiles can be extracted from the dataset. 7 3-D digital documentation may, therefore, be of great value to identify deterioration or damage, for example, before and after loan. ...
... This one is similar to roundness, yet emphasizes the configuration of the perimeter by reflecting the smoothness of contour, rather than the length relative to object area. 21 Shape factor is defined as: E Q -T A R G E T ; t e m p : i n t r a l i n k -; e 0 0 7 ; 3 2 6 ; 6 8 6 Shape factor ¼ 4πA ...
... 21Fig. 23Sources of measurement error that lead to uncertainty of measurement results.21 Journal of Electronic Imaging 011017-14 Jan∕Feb 2017 • Vol. ...
A method is presented for increasing the spatial resolution of the three-dimensional (3-D) digital representation of coins by combining fine photometric detail derived from a set of photographic images with accurate geometric data from a 3-D laser scanner. 3-D reconstructions were made of the obverse and reverse sides of two ancient Roman denarii by processing sets of images captured under directional lighting in an illumination dome. Surface normal vectors were calculated by a “bounded regression” technique, excluding both shadow and specular components of reflection from the metallic surface. Because of the known difficulty in achieving geometric accuracy when integrating photometric normals to produce a digital elevation model, the low spatial frequencies were replaced by those derived from the point cloud produced by a 3-D laser scanner. The two datasets were scaled and registered by matching the outlines and correlating the surface gradients. The final result was a realistic rendering of the coins at a spatial resolution of 75 pixels/mm (13-μm spacing), in which the fine detail modulated the underlying geometric form of the surface relief. The method opens the way to obtain high quality 3-D representations of coins in collections.
Full-text download from institutional repository. http://discovery.ucl.ac.uk/1520053/.
... Although a 3D digital model does not provide a complete representation of the object, it should be understood as a highly powerful tool-potentially, with valid data-for cultural heritage research, and complementary to other measurement techniques (as used in this case study) and fields of knowledge (Moitinho de Almeida 2013). ...
Full book chapter available at:
https://www.researchgate.net/publication/322696760_Beyond_Photography_An_interdisciplinary_exploratory_case_study_in_the_recording_and_examination_of_Roman_silver_coins
