The Camera Obscura

History:
The Camera Obscura (Latin for Dark room) was a dark box or room with a hole in one end. If the hole was small enough, an inverted image would be seen on the opposite wall. Such a principle was known by thinkers as early as Aristotle (c. 300 BC). It is said that Roger Bacon invented the camera obscura just before the year 1300, but this has never been accepted by scholars; more plausible is the claim that he used one to observe solar eclipses. In fact, the Arabian scholar Hassan ibn Hassan (also known as Ibn al Haitam), in the 10th century, described what can be called a camera obscura in his writings.

The earliest record of the uses of a camera obscura can be found in the writings of Leonardo da Vinci (1452-1519). At about the same period Daniel Barbaro, a Venetian, recommended the camera as an aid to drawing and perspective. He wrote:

"Close all shutters and doors until no light enters the camera except through the lens, and opposite hold a piece of paper, which you move forward and backward until the scene appears in the sharpest detail. There on the paper you will see the whole view as it really is, with its distances, its colours and shadows and motion, the clouds, the water twinkling, the birds flying. By holding the paper steady you can trace the whole perspective with a pen, shade it and delicately colour it from nature."

In the mid sixteenth century Giovanni Battista della Porta (1538-1615) published what is believed to be the first account of the possibilities as an aid to drawing. It is said that he made a huge "camera" in which he seated his guests, having arranged for a group of actors to perform outside so that the visitors could observe the images on the wall. The story goes, however, that the sight of up-side down performing images was too much for the visitors; they panicked and fled, and Battista was later brought to court on a charge of sorcery!

How does it work?
Inside the darkened room, a pinhole in the exterior wall acts as a lens, which then creates on an interior wall an inverted projection of what is outside.The camera obscura or dark chamber is a piece of equipment designed to intercept rays of light as they passed through a small aperture which then formed an inverted or upside down image on a screen- neatly demonstrating in the process how light rays travel through the human eye. This happened in the late 16th century when lenses or angled mirrors were first used to re-invert the image, or make it the right way up -doing the job of the retina in the human eye.

Camera obscura (image and object)

Artists use of light in the 17th & 18th centuries owed a great deal to experiments paralleled in the science of optics.(For more on the ideas of Art & Science also see The Parallel Analysis of Vision: Modern Art & Science by Glimcher & Vitz)

Apart from its use as an entertainment medium, it was quickly taken up by artists for optical guidance- reflecting three dimensional objects onto two-dimensional surfaces and simplifying tonal values. The camera obscura changed the way in which artists viewed their work and even how they thought about it. Art was to become direct representation, rather than indirect recreation. Much attention was paid to recording ordinary domestic scenes whose subject matter was greatly enhanced by accurately observed levels of light.