Color & afterimages / 2005
Lilac chaser
A green spot seems to chase colors that begin to disappear.
TRY THIS
Press Play, then hold your gaze gently on the central cross. Watch the moving gap with your peripheral vision. The green spot is an afterimage, not a painted dot.
THE IMAGE IN THIS ARCHIVE
TotoBaggins at English Wikipedia Later versions were uploaded by Howcheng at en.wikipedia.
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Download imageFrequently asked questions
What is Lilac chaser?
A green spot seems to chase colors that begin to disappear.
What should I look for in Lilac chaser?
Press Play, then hold your gaze gently on the central cross. Watch the moving gap with your peripheral vision. The green spot is an afterimage, not a painted dot.
What explains Lilac chaser?
Adaptation to magenta produces a greenish afterimage when a spot disappears. Successive gaps make the afterimage appear to move. With steady fixation, the remaining spots can also fade through a Troxler-like effect.
