A work of art is itself an object, first of all, and so manipulation is unavoidable: it's a prerequisite. But I needed the greater objectivity of the photograph in order to correct my own way of seeing: for instance, if I draw an object from nature, I start to stylize and to change it in accordance with my personal vision and my training. But if I paint from a photograph, I can forget all the criteria that I get from these sources. I can paint against my will, as it were. And that, to me, felt like an enrichment.
Gerhard Richter, Dietmar Elger, Hans-Ulrich Obrist (2009). “Gerhard Richter: text : writings, interviews and letters, 1961-2007”