Munker-White Illusion
PERCEIVING COLOURS:
Colour Interactions
Explore the nature of contextual colour
Details:
All ages
Time: 15 minutes
Learning Outcome: Recognize that the boundaries of an area can affect how you perceive a colour of that area.
Colour Concepts: Colour is contextual. The shape and colour of a boundary can affect how you perceive a colour.
Materials:
Scissors
Crayon (or marker, or pencil crayon - something to colour in a space)
Instructions:
Choose one coloured crayon (or pencil crayon etc.). If you did the Simultaneous Contrast exercise – choose the same colour.
Fill in the areas between the dashed lines in the image (as indicated by the arrows) and also fill in the rectangle at the bottom with the same colour of crayon. Make the colour as opaque as you can.
Hold the paper at arm’s length and squint at the diagram. Notice how the colour of the surrounding stripes and implied boundaries change the perceived colour of each area.
Cut out the coloured rectangle at the bottom and place on top of the illusion, so you are connecting coloured areas from the right and left sides. This will help you verify that the coloured areas all have the same original colour.
Figure 1. Colour in areas indicated by arrows.
Vocabulary:
Questions & observations:
Describe how the colour of the surrounding stripes and boundaries change the perceived colour of each area.
Specifically describe the impact of the black vs. white boundary on the perceived colour.
More to explore:
Repeat the exercise using different coloured crayons. Compare whether the effect is stronger with vivid, pale, muted or dark coloured crayons. Also try grey coloured crayons.
Create your own variations of the Munker-White illusion. See the glossary definition for examples.
What’s going on?
Colour is a perceptual experience, and the coloured objects we see in the world are never viewed in isolation. In the Munker-White illusion, the colours of the neighbouring areas impact the colour we perceive from the areas we coloured with a crayon. Although this illusion seems like the same illusion as Simultaneous Contrast, it is not. Notice that here when white predominates in the adjacent areas, the grey areas appear lighter rather than darker. See the glossary entry on Simultaneous Contrast for a visual example.
Find out more:
For an interactive version and some references for further reading see https://michaelbach.de/ot/lum-white/index.html
Other compelling variations of the Munker-White illusion:
The Confetti Illusion by David Novick (See the Journal of Illusion article by David Novick and Akiyoshi Kitaoka for a deep dive.)
The Green and Blue spirals illusion by Akiyoshi Kitaoka. See his website for many stunning illusions.
