A set of highly moving and rarely seen photographs of life in Poland's Lodz Ghetto are being exhibited at the Nazi Documentation Centre in Cologne.
The photos were taken by the prisoners themselves and capture scenes of everyday ghetto life, such as community dances and boys working in a factory.
There are also horrific images of execution and trains carrying prisoners to their death in the camps.
Until now, the photos were stored in 27 albums holding more than 1200 photos in the state archive at Lodz.
It has only been possible to identify two photographers: Mendel Grosman and Henryk Ross. Grosman was killed shortly before Poland was liberated by the Allies, and Ross kept the images until he emigrated to Israel in 1956.
Dieter Maretzky, the Spokesman for the Nazi Documentation Centre, said: "Two thousand Jewish citizens of Cologne were deported to the Lodz Ghetto. Only 24 survived. We searched for a long time for photos like these."