Mann's technique changed not only in the physical sense of painting but also in his cognitive process of creating images. His memory and imagination became his vision, replacing straightforward observation, and his paintings celebrate this subjectivity. His son Peter created a documentary about his father's adaptive techniques. The restrictions imposed by the reality of vision no longer applied to him, and he remarked that he had complete creative liberation. "I chose the colour chord for each painting intuitively, thinking in an overtly decorative way which, before, I would never have allowed myself to do. It seems that blindness has given me the freedom to use colour in ways that I would not have dared to when I could see."
