Dark Room Forewarning

The Dark Room.  Sign Pictures.

How prescient.

Or is this a gag from the old days of dark room photographic processing?

“Dark room.  Keep door closed!!  If it is left open all of the dark leaks out.”
Image courtesy of http://www.signpictures.net/pictures/The_Dark_Room.htm.

See:

• http://www.signpictures.net/pictures/The_Dark_Room.htm