Hermann Maertens’ Der Optische-Maassstab and the Photography of Architecture

The work of the German architect Hermann Eduard Maertens (1823-1898), and in particular his research on the Optische-Maassstab, results a scientific, geometric tool to link the physiology of vision to the visual harmony of architecture, which was largely considered by urban planners and designers in the 20th century. Based on the concept that distancing is a function of beholder’s specific intents of vision, the Optical Scale proposes a triad of angles, to be measured on the vertical plane to the horizon plane. Although Maertens apparently ignore the photography, both his approach and photography imply a beholder standing still, are unable to describe the growing movement taking place in the cities and take into no account the role of colors and some of the most arbitrary features of his tool may be attributed to a specific interest in early results of photography of architecture, which is the main focus of this article.