Troxler’s fading or Troxler’s effect is a phenomenon of visual perception. When one fixates a particular point, after about 20 seconds or so, a stimulus away from the fixation point, in peripheral vision, will fade away and disappear. The effect is enhanced if the stimulus is small, is of low contrast or equiluminant, or is blurred. The effect is enhanced the further the stimulus is away from the fixation point. Troxler’s fading was discovered by Ignaz Paul Vital Troxler in 1804.
Troxler’s fading has been attributed to adaptation of neurons in the visual system vital for perceiving a stimulus. It is part of the general principle in sensory systems that an unvarying stimulus soon disappears from our awareness.
Patrick Hughes (born 20 October 1939) is a British artist working in London. He is the creator of “reverspective”, an optical illusion on a 3-dimensional surface where the parts of the picture which seem farthest away are actually physically the nearest.
His first “reverse perspective” or “reverspective” was Sticking Out Room(1964), which was a life-size room for the Institute of Contemporary Arts (ICA) in 1970. He returned to explore the possibilities of reverspective in 1990 with Up the Line and Down the Road (1991) Since then, his reverspectives have been shown in London, New York, Santa Monica, Seoul, Chicago, Munich and Toronto.
Patrick explains reverspective:
‘Reverspectives are three-dimensional paintings that when viewed from the front initially give the impression of viewing a painted flat surface that shows a perspective view. However as soon as the viewer moves their head even slightly the three dimensional surface that supports the perspective view accentuates the depth of the image and accelerates the shifting perspective far more than the brain normally allows. This provides a powerful and often disorienting impression of depth and movement. The illusion is made possible by painting the view in reverse to the relief of the surface, that is, the bits that stick farthest out from the painting are painted with the most distant part of the scene’
The picture surface of Vanishing Venice (above) is 3-dimensional, made of two pyramids protruding towards the viewer with the tops cut off: the bases of the pyramids are farthest away (flat against the wall). The two lighter rectangles which appear to be in the distance at the end of the buildings are the flat tops and thus the part of the image physically nearest to the viewer (see diagram below).