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MUHOW WE PERCEIVE COLOUR
The lilac chaser is a visual illusion that demonstrates color adaptation or human visual perception.
It consists of 12 lilac/pink blurred discs arranged in a circle around a small black, central cross on a grey background. One of the discs disappears briefly, then the next, and the next, and so on, in a clockwise direction.
When one stares at the cross for at least 30 seconds, one sees three illusions:
1 A gap running around the circle of lilac discs;
2 A green disc running around the circle of lilac discs in place of the gap; and
3 The green disc running around on the grey background, with the lilac discs having disappeared in sequence.
The chaser effect results from the phi phenomenon illusion, combined with an afterimage effect in which an opposite color, or complementary color – green – appears when each lilac spot disappears.
@mutual_media
