Eariler this year the British released thousands of aerial recon photos of Auschwitz...
http://www.guardian.co.uk/military/story/0,11816,1125188,00.htmlSmoke over Auschwitz, landings in Normandy - unseen allied reconnaissance photos are revealed For £10 you can view "as though in a time machine" a 3D photograph which could have saved hundreds of thousands of lives had it been publicised when it was taken at 11am on August 23 1944, at a time when Hungarian Jews were being murdered below.
The photograph, taken by an RAF reconnaissance pilot and released yesterday, reveals what Auschwitz concentration camp looked like in its climactic frenzy of killing, during which at least 437,000 Hungarian Jewish men, women and children were added to the death toll.
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At the time the Nazi authorities, knowing their defeat in the second world war was in sight, had ordered a steep increase in the tempo of extermination. Crematoriums were overwhelmed and temporary burial pits were fired. Those due to be taken to the gas ovens had to queue for a day in woodland near one crematorium, so the ashes of earlier victims fell on them as they waited. The resolution of the possibly unique aerial image is so good that inmates can be seen on roll call."
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The article didn't note whether there were large equipment transfers visible, but only that there was unmistakeable evidence of the Nazis working overtime which didn't seem to register with Allied Authority at the time.