---
title: Rapid Color Afterimage
date: "2005-06-07T12:00:00Z"
categories:
  - links
wp_id: 644
description: Experience an optical illusion where fixating on a central cross causes rotating magenta patches to leave green afterimages. With steady focus, the original patches disappear entirely, leaving only a single rotating green spot.
keywords: [optical illusion, afterimage, lilac chaser, magenta, color perception, visual system]
---

Michael demonstrates an interesting [Optical illusion](http://www.michaelbach.de/ot/col_rapidAfterimage/index.html).

> On the right you see a circle of blue-violettish (=magenta) patches, one of which briefly disappears, circling around.
>
> Let your gaze rest on the central fixation cross, but observe with your "inner eye" the patches just when they disappear. With good fixation, you should see a strong greenish colour whenever the violet patch has disappeared.
>
> When you are fixating well, after a few cycles you will actually see a rotating green spot! If your gaze is really steady, the magenta patches will disappear, leaving only a rotating green spot!