Enlarge.
My uncle took this picture at the Vietnam Memorial Wall in September 2000. For some reason, my grandma just noticed the ghost-like reflections of soldiers on the granite. At first, I thought it was really a part of the wall. But compare it with this picture from http://vietvet.org/.
And according to the official website, the designer intended for the walls to have “a mirror-like surface (polished black granite) reflecting the images of the surrounding trees, lawns, monuments, and visitors”. There is no mention of photographs placed underneath the granite.
Could those images really be ghosts? Or was it just some sort of trick the developer of the film did?