can be made of wood, though most common com-
mercial tripods are composed of lightweight metal.
Filters
Filters are used over the lens to either create or
negate a particular visual effect. Filters can also be
used to block out a particular color or wavelength
of light, as in UV filters. Color correction filters
can correct a colorcast in a scene, while specialized
filters can create images with starbursts around
lights or other specialized effects.
CHRISTYESissonSeealso:Camera: An Overview; Camera: Pinhole
Camera; Camera Obscura; Exposure; Film; Lens;
Point-and-Shoot
Further Reading
Adams, Ansel.The Camera (Book I). Boston: Little Brown &
Co., 1995.
Kemp, Gregg.The Pinhole FAQ.http://www.pinhole.com/
resources/FAQ/ (accessed 19 June 2001).
Kingslake, Rudolf.Optics in Photography.SPIE (Interna-
tional Society for Optical Engineers).#2000 The Society
of Photo-Optical Instrumentation Engineers.
Langford, Michael.Basic Photography. New York: Focal
Press, 2000.
London, Barbara, and John Upton.Photography. (7th ed.)
New York: Prentice Hall, 1998.
Schaefer, John.An Ansel Adams Guide: Basic Techniques of
Photography, Book 1. Boston: Little Brown & Co., 1992.
Stroebel, Leslie D., ed.Basic Photographic Materials and
Processes. New York: Focal Press, 2000.
Wilgus, Jack and Beverly Wilgus.The Magic Mirror of Life:
a search for camera obscura rooms. http://brightbytes.
com/cosite/collection.html (accessed May 5, 2005).CAMERA: AN OVERVIEW
The camera is in large part responsible for shap-
ing the cultural landscape of the past one hun-
dred years. A camera enables its user to seize a
moment in time and capture it on film or as
digital information. The camera’s final product,
the photograph, allows anyone to become an eye-
witness to these captured moments, whether ‘real’
or manufactured. The pervasiveness of photogra-
phy in world culture is a direct result of advance-
ment in camera technology and manufacture.
Modern cameras are portable and precise,
though their origins date back to ancient times.
Camera Obscura
The predecessor of the modern camera is the camera
obscura (‘‘dark room’’ in Latin). The camera obscura
was often a darkened room, with a small hole in a
window covering. Through the hole, an image of life
outside the window was projected on to an opposite
parallel wall, upside down. This principle had been
known in early Chinese, Arabic, and Greek cultures.
The basic concept behind the camera obscura, and
all cameras, is that light travels in a straight line.
Whenlightraysreflectedoffofasubjectpass
through a hole, they cross and reform. The hole
acts as a point of projection for the image. Any ray
of light that passes through the hole will hit the focus
plane (the wall) at a particular point. Any other ray
of light, again being reflected off of the initial sub-
ject, will intersect at a different point. These multiple
points, when reassembled on the focus plane, form
the image. The distance from the hole to the focus
plane determines the final size of the image.
The discovery of photography in 1827 by Joseph
Nie ́pce and his partner, Louis Daguerre, fostered
the birth of the modern camera. In fact, Daguerre
used camera obscura in many of his early photo-
graphic attempts, but soon employed more portable
cameras such as pinhole and simple lens cameras.Pinhole cameras
Pinhole cameras consist of a light-tight box or con-
tainer with at least two parallel surfaces, with a small
hole in one of those surfaces. The primary difference
between pinhole cameras and camera obscura is that
pinhole cameras use some type of light-sensitive
material (film or photographic paper) to capture
the image and make it permanent. Pinhole cameras
can be made out of almost any container that can be
made to be light tight.
Pinhole cameras, though still in use today, present
some drawbacks, although some photographersCAMERA: AN OVERVIEW