Visual illusion of the change of the size of architectural and urban objects observed upon a change of the observer's distance: Parameters that influence it phenomenologically

Abstract

This paper explores the visual phenomena of a seeming change of the target-object's size (as a focus of concrete visual perception) in the function of an observer's motion so that it 'seems' contrary to the law of linear perspective (in the sense of an expected increase of the target volume/monumentality - by getting closer or a decrease - by getting farther away). This phenomenon is described in a geometrical and perceptual aspect; the result of this comprehensive approach led to identify parameters that determine it phenomenologically. It was established that the explored visual phenomenon is a specific 'size illusion', i.e. an 'angular size illusion' that occurs when influenced by factors of the perceptual kind - activated by a specific dynamic relationship (on a visual plan) between the target object and its surrounding competitive objects, as an observer moves. By understanding the character of this phenomenon (both in a geometrical and perceptual sense), it is possible to apply the acquired knowledge in practice - in programming the visual effects to be obtained (such as to visually optimize or minimize the monumentality of targeted objects) in all architectural and urban fields (planning, designing and reconstruction)

The Impact Of Architectural And Urban Patterns On The Behaviour Of An Exhibited Angular Size-Illusion

“…However, under some circumstances, as the distance changes, the impression of the perceived object's volume does not as described, but inversely. As it has already been confirmed by Djordjevic and Vujic (2010), this occurrence is based on the angular size-illusion influence, due to the impact of specific perceptual factors in the form of distance-depth cues and specific neural activities (Murray et al, 2006). This includes an additional influence of another perceptual factor known as the oculomotor micropsia (McCready, 1965;Komoda and Ono, 1974;Ono et al, 1974).…”

“…This includes an additional influence of another perceptual factor known as the oculomotor micropsia (McCready, 1965;Komoda and Ono, 1974;Ono et al, 1974). This paper continues the research performed by Djordjevic and Vujic (2010), by exploring the impact of various architectural and urban patterns on the behavior of an angular size-illusion noticeable during the observer's continual and uniform movement. It can be understood as a specific casestudy in the field of architecture and urbanism that attempts to explore parameters assumed both as proper illusion quantifiers and qualifiers (such as: descriptors and determinants).…”

“…It confirmed that the paradoxical visual effect related to a seeming size-decrease of architectural and urban objects -noticeable as the observer approaches them, can be treated as the consequence of this angular size-illusion influence. The fundamentals of that illusion were investigated once it appeared in built spaces, together with specific triggering conditions and other relevant descriptors (Djordjevic and Vujic, 2010).…”

“…Because of the nature of this research, starting terms and their meanings are inherited from the already mentioned subject-related research performed by Djordjevic and Vujic (2010):…”

“…Illusion noticeability describes its state of being seen as the marker-to-focus dimensional seeming-change impression, as a consequence of both the observer's movement and the presence of relevant triggering conditions (Djordjevic and Vujic, 2010).…”