Capturing Fine Details Involving Low-Cost Sensors –A Comparative Study

Abstract

ABSTRACT:Capturing the fine details on the surface of small objects is a real challenge to many conventional surveying methods. Our paper discusses the investigation of several data acquisition technologies, such as arm scanner, structured light scanner, terrestrial laser scanner, object linescanner, DSLR camera, and mobile phone camera. A palm-sized embossed sculpture reproduction was used as a test object; it has been surveyed by all the instruments. The result point clouds and meshes were then analyzed, using the arm scanner's dataset as reference. In addition to general statistics, the results have been evaluated based both on 3D deviation maps and 2D deviation graphs; the latter allows even more accurate analysis of the characteristics of the different data acquisition approaches. Additionally, own-developed local minimum maps were created that nicely visualize the potential level of detail provided by the applied technologies. Besides the usual geometric assessment, the paper discusses the different resource needs (cost, time, expertise) of the discussed techniques. Our results proved that even amateur sensors operated by amateur users can provide high quality datasets that enable engineering analysis. Based on the results, the paper contains an outlook to potential future investigations in this field.

First Assessments on Heritage Science Oriented Image-Based Modeling Using Low-Cost Modified and Mobile Cameras

“…The current study aims to investigate the feasibility of large-scale multi-spectral image-based heritage digitization, implementing workflows that utilize low-cost equipment, free/ low-cost SfM approach-based software for 3D modeling and free software for point cloud manipulation and post-processing. As mentioned, recent bibliography provides several case studies evaluating smart phone and low-cost digital cameras for heritage VIS 3D modeling (Rehany et al, 2017;Santagati et al, 2017) but the non-VIS products are seldom evaluated from a metric point of view; as has been performed for more complicated and expensive spectral acquisition/ photogrammetric reconstruction scenarios (Mathys et al, 2019). Therefore, this study also addresses in detail all parameters of the sensors utilized, acquisition and processing workflows implemented, and performs an extensive comparison on the geometric and the radiometric characteristics of the three-dimensional results produced.…”

A Review of Photogrammetry and Photorealistic 3D Models in Education From a Psychological Perspective

“…This technological approach has achieved results comparable to those of the previously established method of laser scanning (Kersten et al, 2015;Rehany et al, 2017). Additionally, the workflow is more efficient than traditional 3D modeling (Esmaeili et al, 2017), and the degree of realism can be further enhanced through post-processing (e.g., antialiasing, shadows, or depth of field; Rademacher et al, 2001;Sugano et al, 2003;Kan and Kaufmann, 2012).…”

Multi-Camera Workflow Applied to a Cultural Heritage Building: Alhambra’s Torre de la Cautiva from the Inside

“…Although positive results had been reported with mobile devices [35,36] (which is later than our data collection), much of the success of the work depended on the flexibility and reliability of the cameras in capturing, and therefore the cell-phone option was ruled out. We considered cell phones as offering insufficient and unreliable control over exposure in the conditions in which we had to work, which we would still argue today An additional challenge was the time that was available for data capture, only ten hours spread over one afternoon and the following morning, which was a key factor in choosing the method with which to carry out this task.…”

“…Although positive results had been reported with mobile devices [35,36] (which is later than our data collection), much of the success of the work depended on the flexibility and reliability of the cameras in capturing, and therefore the cell-phone option was ruled out. We considered cell phones as offering insufficient and unreliable control over exposure in the conditions in which we had to work, which we would still argue today [36].…”