CameraObscura.jpg

Photo from Mauricio Acial on Flickr

The camera obscura was the forerunner of the camera. Essentially, it is a darkened room with a hole in its wall. The image that comes through the hole or lens is projected onto the opposite wall, upside down and backwards.

HongKongCameraObscura.jpg

Photo from Sgrah

On Flickr, you can find some neat examples of camera obscura photography. Check out the group Big Room Camera Obscura.