This is another shot taken at The Henry Ford Museum in Dearborn, Michigan. This is a portion of a water turbine and electric generator. It was originally installed in Spokane, Washington in 1903, and ran until 1990. It supplied power to silver mines 100 miles away in Idaho. I really liked this gear and the shear size of the whole thing.
The device was painted in battleship gray so I converted the image to black and white. I also used a dodge/burn layer to make the metal cover in the background a bit darker. I wasn't able to do much about the bright light on the top left. I also added a bit of grain to the image to give it just a little more character.
More processing details here