Thomas Ruff is one of the most internationally well known contemporary German photographers. Over the course of two dozen photography series, he has explored and defined the mediums limits like no other contemporary artist. The catalog focuses specifically on four of Thomas Ruffs series: the "stars" series, produced between 1989 and 1992, "zycles" from 2007, the "cassini" series from 2008/2009, and recent work from the "ma.r.s." series, shown now for the first time in an institutional context. Individual works from other series that explore a similar theme are also shown. Since 1989, Thomas Ruff stopped taking and printing his own photographs in order to work with existing materials. His work is primarily concerned with questions that investigate the structure and content of the medium. Scientific images are the source material for all the photographs shown, and many of them were freely accessible via the internet. While Thomas Ruffs work for the stars series was limited to selecting details from photographs, he took a heavier hand in processing the source material in his new series: for the "cassini" and "ma.r.s". series, Thomas Ruff utilised pictures from various NASA missions. He digitally retouched them, altered the colours, manipulated contrast and cropping. Ruffs colouration of the original realistic, black and white pictures gives them a new character: they become painterly, aesthetic pictures whose abstract beauty serves as a surface for our imaginations. More than any other contemporary artist, Thomas Ruffs work poses questions about the mass production of images. What can an image actually say today and in what ways do we read it? The purpose of image archives and the internet are also central themes of his work, as well as questions pertaining to contemporary artistic license.