Having had no formal academic training, Calderara experimented with different artistic styles up into the late 1950s. The milky landscape of the Orta lake, where the artist lived for decades, became his favourite subject in the course of his search for individual artistic expression. His work became increasingly abstract; finally landscape and architecture disappeared completely. Calderara painted his first abstract work in 1959. From then on he developed a delicately coloured abstract style. For his own geometric method Calderara coined the term "spazio mentale", the mental space. What sets him apart from proponents of constructivism and concrete art is that in spite of his systematic approach, he does not follow radical concepts or colour systems, but paints intuitively.