There are a few websites saying that Falter magazine have obtained the original photos that were what Stangl originally said was taken from the summit of K2. The photos were somehow leaked to them. These photos reveal that the photo that he showed the world initially was manipulated and changed in Photoshop.
In September Stangl came out and admitted that he did not make the summit of K2. He said that pressure to succeed and stress had caused him to hallucinate making the summit of K2. He said later that the photo that he showed the world was instead taken at camp 3. But he said it was not manipulated and was taken on the date that he said.
The background in the original photo showed Chogolisa in the background. The Falter photos though do not have this background and show the background to not look like a summit photo at all apparently.
The date of the photo was also different. Falter apparently claims that it was taken on the 6th of August and not the 12th. This was a period when a number of climbers were going up the mountain. Those on the Cesen route made it to camp 4 and beyond. Those that were climbing up the Abruzzi Spur, like Stangl was, were held back by bad weather around camp 3.
This site was the first one to reveal that the photos had been manipulated. The unusual lines running down the left hand side of the photo gave a strong indication that the photo had been manipulated in a photo editor. Also the EXIF information from the photo showed that Photoshop 7.0 had been used to produce the jpeg final image.
The Falter revelations also back up Maxut Zhumayev and Torok Zsolt’s account that Stangl never even climbed up the Abruzzi Spur on the dates that he said he did.
When these original photos are made more widely available then these claims allegedly made by Falter could be verified. If they do have the original photos it would be further damning to the reputation of Stangl.
Source: Tages Anzeiger Google translated from German
Source: Der Bund Google translated from German
Kurier Google translated from German
This sites analysis of manipulation of the photo