Editing Contrast effect (section)

=== Successive contrast ===
Successive contrast occurs when the perception of currently viewed stimuli is modulated by previously viewed stimuli.<ref>Chevreul, Michel Eugène (1839). ''De la loi du contraste simultané des couleurs et de l'assortiment des objets colorés'' – translated into English by Charles Martel as ''The Principles of Harmony and Contrast of Colors'' (1854) and by Dan Margulis as ''On the Law of Simultaneous Contrast of Colors'' (2020)</ref><ref>Hermann von Helmholtz: ''Handbuch der physiologischen Optik'' section II § 24: ‘Genauer unterscheidet Chevreul die hierher gehörigen Erscheinungen unter dem Namen des ''simultanen Contrastes'' von denjenigen, wo zwei Farben nach einander auf derselben Netzhautstelle erscheinen, welche er mit dem Namen des ''successiven Contrastes'' belegt.’</ref> In the example below you can use the scrollbar to quickly swap the red and green disks for two orange disks. Staring at the dot in the centre of one of the top two coloured disks and then looking at the dot in the centre of the corresponding lower disk makes the two lower disks briefly appear to have different colours, though in reality their colour is identical.

<div style=color:black;background:black;height:9em;overflow-y:scroll;width:24em;margin:auto><div style=padding:4em;text-align:center;><span style=background:#f00;padding:3em;border-radius:9em>•</span> &nbsp; <span style=background:#0b0;padding:3em;border-radius:9em>•</span></div><div style=padding:4em;text-align:center;><span style=background:#d80;padding:3em;border-radius:9em>•</span> &nbsp; <span style=background:#d80;padding:3em;border-radius:9em>•</span></div></div>