The Isometric System

Christine and I received an excerpt from the Phoebe McNaughton’s Perspective and Other Optical Illusions describing the isometric system – the all in one hexagonal projection. This method is a specific case of oblique projection and requires only one viewpoint from which the entire illustration is seen. The three axes within the illustration are then equally foreshortened and within the hexagonal grid is separated by 60 degrees. This method was normally used for mechanical and engineering plans. It helped convey a more three dimensional appearance to the two dimensional drawing. Oscar Reutersvard utilized this method to create such works of art as the Penrose Triangle, which is an impossible, optical illusion. The corners of the triangle connect at impossible angles which illustrates the ‘isometric depth ambiguity’. Another example of this method can be seen in Schroeder’s reversible staircase.