Quantifying the density-quality of photogrammetrically created point-clouds of linear architectural/urban elements as a function of shooting distances and number of camera positions I.E. shooting-directions

Abstract

This paper examines the impact of various object-to-camera distances and the number of station-points i.e. various shooting directions with regard to the obtained Density-quality of photogrammetrically created Point-clouds - as digital representations of the existent linear architectural/urban objects/elements. According to an artificial (purified) experimental scene used, the conclusion is that with the chosen focal lengths/object-to-camera distances, with shooting directions perpendicular to the axis of that object, with station-points uniformly radially distributed around it (at a circle of 360deg), and with the obtained values of photogrammetric-software process-quality outputs which belong to the recommended ranges, the achieved density-level of the created Point-clouds may be treated as independent on the camera's radial-movement angle but dependent on the percentage of ?Object's Photo-Coverage?: the lower the Coverage, the lower the density. Also, regardless of the Coverage level, the majority of the generated points are generally more "densimetrically" precise than they are "densimetrically" accurate.