A hybrid between analogue and digital: the viewer can — or must — reverse the printed negative colour photographs with a smartphone, becoming a developer in their own digital darkroom. The theme is politically explosive: images, still taboo in China, of the 1989 protests on Tiananmen Square in Beijing. As Markus Schaden, founder of the Photobook Museum, writes, it is an outstanding concept by the Chinese photographer that shows how the photobook has arrived in the new decade.