Colour Phenomena

After reading the article "Phenomenal Illusions" on the "Phenomenal Qualities" blog I became to understand more about  the importance and impact of a colours surroundings and not just the focus of the base colour and the way it can alter colours in the same composition.

Square A and B are actually the same Hue, this is altered by the adjacent squares. (Deconstruction of the image below)

Deconstruction of the illusion 

Michel Eugene Chevreul whilst working at Gobelins Manufactory as the "Dye Directer". In his study "The Principles of Harmony and Contrast of Colours" he goes on to talk about other phenomena such as Successive Contrast or Negative Afterimages. This is when "...two colour areas are seen close together in space or time, each will shift in hue and value as if the visual complementary colour of the neighboring or preceding colour were mixed with it."  

This is to say when you view one hue then view a second different hue you perceive the colours mixed.

Simultaneous Contrast Illusion. The background is a colour gradient and progresses from dark grey to light grey. The horizontal bar appears to progress from light grey to dark grey, but is in fact just one colour.

Phenomenal Illusions: http://phenomenalqualities.wordpress.com/phenomenal-pictures/

The Principles of Harmony and Contrast of Colours by Michel Eugene Chevreul: http://www.handprint.com/HP/WCL/chevreul.html