Three Points of View for the Drawing Adoration of the Magi by Leonardo da Vinci

This contribution to the literature presents an in-depth analysis of the scene drawn by Leonardo da Vinci in the preparatory drawing, Adoration of the Magi, dated 1481, that is now housed at the Département des Arts Graphiques du Musée du Louvre in Paris, France. This analysis focuses on the architectural elements and highlights how the drawing discloses three distinct vanishing points/centers of vision: one for the classical architecture to the left of the scene, one for the Nativity hut, and one for the structure with stairs. If we consider the structures as belonging to the same 2D projected space, at least two must be depicted out of square; conversely, if we consider them as straight, standard structures, they cannot belong to the same 2D projected space. Given this assumption, we propose, on the one hand, some variations of the scene where the structures are straightened and projected according to only one of the viewpoints at a time; on the other hand, a set of variants of the scene are presented, considering the out-of-square structures. The scenes are generated by applying inverse perspective projections. These results prompt a discussion on possible reasons why Leonardo made these conscious or unconscious “formal errors”.

Jan van Eyck's Perspectival System Elucidated Through Computer Vision

It is generally accepted that Jan van Eyck was unaware of perspective. However, an a-contrario analysis of the vanishing points in five of his paintings, realized between 1432 and 1439, unveils a recurring fishbone-like pattern that could only emerge from the use of a polyscopic perspective machine with two degrees of freedom. A 3D reconstruction of Arnolfini Portrait compliant with this pattern suggests that van Eyck's device answered a both aesthetic and scientific questioning on how to represent space as closely as possible to human vision. This discovery makes van Eyck the father of today's immersive and nomadic creative media such as augmented reality and synthetic holography.

In a Slant Light: A Poet’s Memoir, Cilla McQueen (2016)

Review of: In a Slant Light: A Poet’s Memoir, Cilla McQueen (2016) Dunedin: Otago University Press, 134 pp., ISBN 978 1 87757 871 7 (hbk), NZ$35 Fale Aitu / Spirit House, Tusiata Avia (2016) Wellington: Victoria University Press, 84 pp., ISBN 978 1 77656 064 6 (pbk), NZ$25 Vanishing Points, Michele Leggott (2017) Auckland: Auckland University Press, 132 pp., ISBN 978 1 86940 874 9 (pbk), NZ$27.99 Tightrope, Selina Tusitala Marsh (2017) Auckland: Auckland University Press, 112 pp., ISBN 978 1 86940 872 5 (pbk), NZ$27.99 Night Horse, Elizabeth Smither (2017) Auckland: Auckland University Press, 80 pp., ISBN 978 1 86940 870 1 (pbk), NZ$24.99

RESECTION AND MONTE CARLO COVARIANCE FROM VANISHING POINTS FOR IMAGES OF UNKNOWN ORIGIN

Photogrammetric analysis requires camera metadata (position, attitude, interior orientation, etc.), which is not available for all images. Modern commercial solutions for 3D reconstruction from images typically assume large amounts of purposefully-collected, highly-overlapping imagery. In this article, a system is demonstrated for recovering a 3D scene from images of unknown origin, by marking ground space axes, resecting a camera consistent with the markings, and then using the solved camera to collect 3D measurements. The capability works with close-range (vanishing points) and long-range (parallel axes) imagery. Monte Carlo analysis is used to propagate measurement uncertainty of the vanishing lines to uncertainty of exterior and interior camera parameters, which can then be used to quantify uncertainty of measurements in the 3D scene.