Katja Mater’s series ‘Time is an Arrow, Error’ entails layers of duration. The process begins with a drawing of half an analogue clockface. The drawing is then photographed in natural light, producing two separate negatives that each capture the image over different extended exposures. Subtle shifts in light lead to variations in colours and, in some cases, the uneven transcription of shadows on the photographic plate. Finally, one of the two semicircles is flipped or rotated, resulting in a whole clock formed by two irregular halves. The steady passage of mechanised time is thus expressed in imprecision and irresolution. Designed by Elisabeth Klement and with a text by Amelia Groom.