The gaps between the leaves of a tree work like a giant pinhole lens, with a focal length of many feet. The images of the eclipsed sun on this climbing wall are about 8 to 10 inches in diameter. May 20, 2012.
The gaps between the leaves of a tree work like a giant pinhole lens, with a focal length of many feet. The images of the eclipsed sun on this climbing wall are about 8 to 10 inches in diameter. May 20, 2012.