History Of Cameras

or more than several decades the box camera (viewfinder) was the instrument of choice for the casual amateur photographer. Inexpensive and simple, it was, nevertheless, capable of excellent results under many conditions. Box cameras were normally fitted with a single-element lens, a limited range of aperture control, and a single-speed leaf shutter.Ð' Ð' The Folding-Roll Film CameraÐ' Second in popularity only to the box camera, the folding camera was manufactured in a variety of formats. Basically, though, it was a box camera whose lens was incorporated into a movable bellows that could slide back and forth on a rail, allowing the lens to change focus

s. Lenses and shutters were often one-piece units. More elaborate models were first-rate instruments with high-quality optical systems

and precision shutters. Many were fitted with coupled rangefinders. The most significant advantage they have over the box camera, however, was their compact design when folded, which made them easier to pack and transport.Ð' There has been something of a minor renaissance in folding-roll film cameras in recent years, with appearance of several new professional instruments. They are appreciated for their large negative size and compact design.Ð'

Range Finder Camera - Similar to a Viewfinder type camera this camera does not use a lens to view the subject but instead relies on a separate viewing system in the camera for aiming and for focus.Ð' The range finder camera allows for accurate focus, however, by using two views of the same subject to adjust focus. In this camera there are two images in the viewfinder. One is usually only a portion of the viewer area and is usually slightly yellowish in color. The photographer adjusts the focus ring on the lens and as they do the two images move. When both on directly on top of each other they blend together and almost disappear signifying the camera isÐ' in focus.Ð' The rangefinder is accurate and usually very quiet and very light weight.Ð' It is useful for taking pictures in low light conditions or for candids when quiet is important. These cameras can easily be identified by their double view windows in the front.Ð'

Twin-Lens Reflex CamerasÐ' A medium-format camera--one that uses film larger than 35mm--the twin-lens reflex was immensely popular after World War II. It is fitted with two lenses of identical focal length, one mounted atop the other. The lower, or taking, lens focuses its image directly on the film, while the image produced by the upper viewing lens is reflected through 90 degrees by a mirror, and brought to focus on a horizontal ground-glass focusing screen. The light paths to the film plane and the focusing screen are equal, so that if the photographer brings the scene on the focusing screen to sharp focus, the image on the film plane will be equally sharp.Ð' Ð' Ð' Ð'

Single-Lens Reflex CamerasÐ' One of the most popular designs available today, the single-lens reflex (SLR) both views and photographs through one lens. Light passing through the lens is reflected by a mirror and brought to focus on a ground glass. The mirror causes a reversal of the image seen on the ground glass, but the addition of a pentaprism mounted over the ground glass allows the camera to be used at eye level, with the image seen upright and in proper left/right orientation. An instant before the exposure is made, the mirror swings upward, and the shutter is activated. A single control cocks the shutter for the next exposure, advances the film, and returns the mirror to focusing position.Ð' Ð'

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View Cameras and Technical CamerasÐ' Cameras in this category are used almost exclusively by professional photographers. The most common film formats are 4 x 5 or 8 x 10 inches, the latter often used in the very large cameras found in portrait studios. Film for these cameras is loaded in the darkroom into two-sided holders, which are inserted at the back of the camera. Both the camera's back and front can be tilted in various positions, to permit the photographer to make certain types of corrections in the image. By raising the lens in relation to the film plane, when photographing a tall building, for example, the tendency for parallel lines to look as if they converge is eliminated.Ð'

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Ð' Instant Cameras An instant camera will produce a finished print in from 20 seconds to about 4 minutes. The film, after exposure, is passed between two stainless steel rollers inside the camera. These rupture a chemical pod on the film and spread developing agent evenly over the film's surface. In the original Polaroid system it was necessary for the user to peel the finished print from the base material. Professional Polaroid films, both color and black and white, are still developed in this manner.Ð' Beginning in 1972 with the all new model, the SX-70, Polaroid Instant Cameras