17mm TSE...it was almost dark...very hard to set the lens tilt, etc. 5DIII is amazing!
How many exposures did you take? 3?
I think I shot 7 exp. to preserve the highlights around that back door....the image is misleading due to the sensor's ability to record near darkness in the foreground compared to the bright highlights of the sun around that back door.
The dynamic range was extreme.
Did you use photomatix?