Although Auschwitz may be the most notorious of the Nazi death camps, there are only a small number of known photos of the place before its liberation in 1945... Rather than showing the men performing their death camp duties, the photos depicted, among other things, a horde of SS men singing cheerily to the accompaniment of an accordionist, Höcker lighting the camp's Christmas tree, a cadre of young SS women frolicking and officers relaxing, some with tunics shed, for a smoking break.... The photos provide a stunning counterpoint to what up until now has been the only major source of preliberation Auschwitz photos, the so-called Auschwitz Album, a compilation of pictures taken by SS photographers in the spring of 1944 and discovered by a survivor in another camp. Those photos depict the arrival at the camp of a transport of Hungarian Jews... The comparisons between the albums are both poignant and obvious, as they juxtapose the comfortable daily lives of the guards with the horrific reality within the camp, where thousands were starving and 1.1 million died. [link]
The online exhibition on the museums webpage contains many of the photos, and an introduction by the archivist.
Important stuff. At a conference, I once asked someone who was collecting oral history about the Holocaust why they were only collecting testimonies from the victims, rather than the perpetrators. Their reaction suggested that this question should not be asked in polite society.