David Von Pein put up this image of Blackie Harrison's eyes to show that blackening of the eyes could take place in those lighting conditions.
But, let's go in a little closer.
Uh oh. It's starting to look non-photographic, isn't it. As in: fake.
Doesn't it look like somebody took a felt pen and went across his eye with it? What reason do you have to believe that that is a legitimate photographic image?
The truth is: how could ANYTHING cast a shadow in that shape and in that location?
But, here's an idea: get your camera out, David, and try to duplicate it. You can duplicate the conditions. Can't you? I tell you though: I think you're in for a rude awakening. You'll never duplicate it because it isn't real.