The
concept of the Pinhole camera, relates to the camera
obscura where there is literally only a light tight box with a
small pin hole opening to project the light onto the film. Images
made with pinhole cameras have a unique aesthetic and many people
still make and use cameras like this to create images.

I
used this technique for the work "Carbon
Obscura", where I drew a landscape image with
thousands of tiny pinholes punched through sheets of carbon
paper that let the sunlight penetrate a darkened space.

Image
reversal

Mouse over image

The
rays of light reflected from an object enter through the pin
hole and reform on the plane at the back of the camera to form
an image. But in the process the rays cross over (laterally
reversed) and the image is formed upside down and reversed left
to right. We can see the top of the tree reforms at the bottom
of the camera. This principle also holds for all cameras with
lenses as well.