What I learned in school (in Germany) was, that many Germans back than claimed that they didn't know about the camps. But it's actually quite hard to tell if that's true today. A common opinion is that a lot of people didn't knew but also that soldiers and other involved Nazis claimed it so they won't get punished.
The reaction on the photograph is more than understandable. Even people who were involved in some of the things that happened in the camps (for example the transportation towards the camps) were maybe or probably not aware of every horrible detail. But I am sure that those documentations the Allies made and forced the Germans to watch were very graphic and as detailed as possible.
I also heard of guided visits to concentration camps which were organised by the Allies. But I am not sure if one could "visit" the camps optionally or if they were forced as well.
The reaction on the photograph is more than understandable. Even people who were involved in some of the things that happened in the camps (for example the transportation towards the camps) were maybe or probably not aware of every horrible detail. But I am sure that those documentations the Allies made and forced the Germans to watch were very graphic and as detailed as possible.
I also heard of guided visits to concentration camps which were organised by the Allies. But I am not sure if one could "visit" the camps optionally or if they were forced as well.