Liquid Light was hand poured on a 4x5 glass plate; it looked flat, but there was a thicker part that resisted development. The plate was shot in bright daylight, however, I forgot to close the shutter. I was surprised when the shutter didn't fire, "What the heck?!" oops. It was developed anyway. I wanted a teaching tool to show a fully developed black plate. Development was in full strength D-76 for 13 min and stopped so I could still see through the remaining light spot. Was I ever surprised to find an image in that blackness.