For a German filmmaker tackling a film on this subject must have been a great responsibility.
I felt it much more while I was preparing the film. As soon as you shoot the movie, you deal with the responsibility in every set up, but you can't let yourself be carried away by that. It's a step-by-step process. But preparing it was really tough. And of course it's not a pleasant subject to deal with. As a civilised human being these are things you hate and detest. Nevertheless you have to dig deep and that's not pleasant.