Pinhole Photography

A camera has a few simple components: A light tight box Aperture – A hole through which light enters the camera. Shutter – A way to control how long light enters the box. Lens – A way of focusing light for a sharp image. Viewfinder – A way to aim the camera. Film Holder – A way to hold the film in the correct place to receive the focused light.

A pinhole camera is the most basic image forming device in photography. It is a direct descendant of the camera obscura, (Latin for “darkroom”). The camera was actually a large room that would be entered by the user.

Light entering a small hole in a darkened room produces an inverted image on the opposite wall. It was used initially to view solar eclipses, but by the seventeenth century the process was made portable by fitting a lens to one end of a box and using a sheet of glass at the opposite end to view the image. A mirror inserted inside at a 45 degree angle would reverse the image, giving the viewer a corrected orientation. giving the viewer corrected orientation.

Sir David Brewster, a Scottish scientist, coined the word "pinhole“and was one of the first to make pinhole photographs in the 1850s.

Instead of a lens, the camera has a small hole that admits light. The image is not as sharp as one formed by a lens, but the entire field of view has an equal degree of sharpness.

A pinhole camera has nearly infinite depth of field. Everything in the photo is in focus.

Only a few light rays from each point on the subject can get through the tiny opening and reach the film in small clusters that cause minimal blurring. rays

A larger hole permits a greater number of rays from each point on the subject to enter the camera. These rays are recorded as large circles which tend to overlap each other, creating an unclear image. They are called circles of confusion.

Straight surfaces may look curved if the film plane is curved.

This image was made from a camera with six pinholes.

A nineteen hole camera.

Any deviation from round will affect the sharpness and the perspective of the image. An oval or short slit will smear the image in the direction of the longest dimension.

Horizontal front slit, with a vertical back slit.

A pinhole camera can be made out of just about anything. This one is made from a red bell pepper, which acts as a safelight for paper.

Sources ~stewoody/photo.htm /gallery1.html Renner, Eric,Renner, Eric, Renner, Eric Pinhole Photography: Rediscovering a Historic Technique. Focal Press, Boston. Upton, Barbara and Upton, John Photography. Little, Brown and Co., Boston.