When is a picture not a picture? What is really in a Random Tandem?

Simon Bexfield
Bridges Donostia: Mathematics, Music, Art, Architecture, Culture (2007)
Pages 389–394


Random Tandems allow hidden pictures. They are a pair of overlaid random dot images. The hidden picture is revealed to a person in the right place at the right time allowing a private viewing experience. Sometimes there is a delight in not showing the viewer the whole picture right away, and as it were tiptoeing up behind him and saying “Boo!”. Random dots allow you to do something special.