Josef Müller-Brockmann. Opernhaus Zürich, Spielzeit 1971/72

“In accordance with Moholy-Nagy's theory, photography had hitherto benn seen as the most objective form of pictorial representation. For the first time, in the early 50s, photographers started to research the potential of subjective perception, combining their personal interpretations of reality with phototechnical experimentation. This new approach was established as an artistic discipline mainly in Germany and was known as 'subjektive fotografie'. Müller-Brockmann experimented with light painting and non-representational photograms for various design commissions.”

Lars Müller (ed.). Josef Müller-Brockmann, designer: a pioneer of Swiss graphic design. Baden: Lars Müller, 1995 (p. 31)