How To Make a Room-Sized Camera Obscura

Step 1: Darken a room - spray windows with water, then apply foil sheets to the wet glass. Step 2: Cut a circular hole in the center of the foil. Start with a large hole, about fist-sized. Step 3: Observe the light coming into the room, and try to figure out what you see. Step 4: Add a new, smaller hole over the fist-size hole. Observe how the projected image changes when the hole size is reduced. Step 5: Keep adding sequentially smaller holes to the window, until the image is too dark to see. Step 6: Wait 5 minutes in the too-dark room, and your eyes will adjust to the new light level. Step 7: Enjoy the outdoors, inside.