Hein Gravenhorst begins working on his computer-generated images with one or two base models, which are then developed further in various ways. One approach is through translation, where the base models are expanded horizontally or mirrored. Another method involves rotation, transforming the base models into circular patterns. In some works, he combines both techniques, utilizing both translation and rotation. These computer-generated images are now being released as NFTs and represent a genuine continuation of his artistic output since the analog masterpieces. Hein Gravenhorst's exhibition at EXPANDED.ART in collaboration with Photo Edition Berlin is a unique opportunity to rediscover a key body of work from the Generative Photography movement of the 1960s. Gravenhorst's approach involves photomechanical transformations that emphasize the creation of images over mere representation. His work stands out for its methodical and systematic approach, embracing mathematical principles such as translation and rotation, and transforming these into visually stunning compositions. Central to the exhibition is the exploration of light and shadow, a fascination that began with the interplay of light through a wine glass, capturing the delicate nuances on photographic paper. This initial experimentation evolved into complex arrangements that reflect principles of Op Art, where geometric clarity and precision play with the viewer's perception. The resulting images are not just photographs but intricate constructs, where light is meticulously shaped into abstract, optical forms. These works, produced through analog techniques such as multiple exposures, showcase a precision that predates digital manipulation yet resonates with contemporary digital aesthetics. Their alignment with the principles of Generative Aesthetics, as conceptualized by philosopher Max Bense, places them at the intersection of art and science, challenging traditional boundaries between artistic intuition and technical method. Gravenhorst’s works, with their rhythmic patterns and structural rigor, invite viewers into a meditative experience, blending visual delight with intellectual engagement—a true homage to the Op Art movement's legacy of creating dynamic visual experiences. In 1968, Gravenhorst, Kilian Breier, Pierre Cordier, and Gottfried Jäger presented the exhibition Generative Photography at the Kunsthaus Bielefeld. They consciously avoided depicting reality and instead developed a constructive, non-representational visual language through chemical and photographic experiments like chemigrams and luminograms. Their work bridged the gap to the computational art of their time, with rationality and systematic methods at its core. Since 2001, Gravenhorst's works have been created exclusively digitally. He refrains from using titles or descriptions, considering the images as "energy fields" that engage in a spiritual connection with the viewer. For him, it is crucial that the images reveal their impact through deep observation. "I would like my pictures to be allowed to speak for themselves, and their effect to be realized in the viewer by 'looking at them properly.'" – Hein Gravenhorst, July 2022