Septette is an example a biangular viewing graphic in which the colours change depending on the orientation of the prism. In this example, the prism can be held either horizontally or vertically. When the prism is held horizontally, the outer septette is blue and yellow and the inner septette is cyan and red.

Howeve, when the prism is rotated 90 degrees counter clockwise from the horizontal position, the colours change and the the outer septette turns red and cyan while the inner septette turns blue and yellow… completely opposite of the horizontal viewing angle.