Historical camera types

Transcription

1 Historical camera types Table of content 1 Box cameras Folding cameras Spring cameras Subminiature cameras Baseboard cameras Reflex cameras Folding reflex cameras Reflex box cameras Single Lens Reflex cameras (SLR) Twin Lens Reflex cameras (TLR) Viewfinder cameras Rangefinder cameras Tube cameras Last changed: 5. Nov Page 1/5

2 1 Box cameras The box camera is a very simple form of the roll film camera. It could be specified by the very common form of the housing. It usually looks like a small box. That is, where term came from. Later, the form of the boxes were a little bit different due to the possibilities of the used plastics. Box cameras were very cheap and often very simple meniscus lenses and simple view finders were used. Seldom, there were models with an extended range of functionality like aperture setting, focusing possibilities and so forth. Well known are, for example, the Kodak Brownie cameras or the Box Tengor made by Goerz and later Zeiss Ikon. Abbildung 2: Box camera Abbildung 1: Spring camera / Folding camera 2 Folding cameras On a folding camera, the shutter and the lens are mounted on special metal arms to the body. The camera could be folded and both of them are hidden by a cap or something like that. If the user opens the camera, the shutter automatically moves to the correct position (usually the infinity focus position). The way of the light is hidden by a folding bellow. The focus is set directly on the lens, because the movement of the shutter itself (as is done on baseboard cameras) is not possible. To open the camera, the power of the user is used exclusively without the help of any springs. Here they differ from spring cameras. 2.1 Spring cameras Spring cameras are a subgroup of the folding cameras. Additionally, they have a built-in spring mechanism, that allows to open the camera automatically without any human power (except to press the appropriate button). So the camera could be used very fast. At a first glance, it is usually not noticable, wether the model is a usual folding or a spring camera. 3 Subminiature cameras The subminiature cameras are known especially by the MINOX series. They use a negative size of 8x11mm. The material is used like a small roll film. Subminiature cameras can be specified by their very small and often even flat form. Without the use of the small film material, they would belong to the standard viewfinder cameras. Last changed: 5. Nov Page 2/5

3 4 Baseboard cameras On this type of camera, the guidon that holds the shutter and the lens, is mounted to a system of rails on the baseboard of the camera. After opening the housing, the guidon must be pulled out to a special point, which mostly is the infinity focus position. To focus the camera, the guidon is moved forward and backward. Some cameras uses double and triple extension baseboards to work in the near field. Abbildung 3: Reflex box Abbildung 4: Baseboard camera 5 Reflex cameras On a reflex camera, the picture is reflected by a mirror to the viewfinder. So, the parameters of the camera (like sharpness and picture position) could be set easily. Before recording the picture, the mirror is usually moved to a resting position. Doing so ensures, that all the light reaches the film. But here, there are some exceptions to the rule (i.e. TLRs or cameras with semipermeable mirrors). There are several sub types of the reflex camera, that are described in the next chapters. 5.1 Folding reflex cameras The folding reflex camera uses exactly the same principle as described in chapter 5. The difference is a mechanism, that allows to fold the camera and so decrease its size. Doing this, the camera could be easily carried or stored. 5.2 Reflex box cameras Reflex box cameras are quite similar to the usual box cameras. But they have a mirror inside to reflect the light that falls through the lens to a viewfinder. Often, the common eyes of the viewfinders of usual box cameras are missing here. In a broader sense, reflex box cameras belong to the single lens reflex cameras. But the common box style is very noticable, too. Compared to the usual SLR cameras, the reflex boxes are quite old. Of course there are some models of both types that were made side by side over the years. 5.3 Single Lens Reflex cameras (SLR) In those cameras, the light of the main lens is reflected to the viewfinder. In most cases, the mirror is movable and panned out of the way of the light directly before taking the picture. In common, the term SLR is used for a camera with a form that differs from a reflex box. Usually, cameras that were built after 1945 were described as SLR. But there are also some cameras, where the mirror is not movable. An example is Last changed: 5. Nov Page 3/5

4 the GSK SR899 that was made by Pentacon Dresden. In this camera, a semipermeable mirror is used to keep the camera silent. The light is partially reflected to the mirror and the film at the same time. This method is nowadays used in some digital cameras, too. Abbildung 5: Single lens reflex camera (SLR) Abbildung 6: Twin lens reflex camera (TLR) 5.4 Twin Lens Reflex cameras (TLR) The twin lens reflex camera owns a second lens that is responsible only for the viewfinder. Those lenses are usually not as fast as the main lens and even their quality is not as high as the taking lens. The picture in the viewfinder was reflected by a static mirror. TLRs can be identified by their two eyes. The form of the camera is usually very high. Typical examples of TLRs are the well known types of Rollei cameras or the Ikoflex series made by Zeiss Ikon. 6 Viewfinder cameras The definition of the term viewfinder camera says, that there exists a special device that allows to position the object within the frame. This device is most often an optical device. The main lens of the camera is only used to guide the beams of the light to the film or sensor plane. But with this definition, nearly all cameras are viewfinder cameras. But in common, the term is used for compact cameras that have an additional window for the viewfinder, that does not depend on the main lens. This window is most often placed either in the upper middle or one of the upper corners of the cameras. On simple viewfinder models, the setting of the object distance is done completely by hand without any additional tools. Abbildung 7: Viewfinder camera Abbildung 8: Messsucherkamera (2 Sucherfenster vorn) Last changed: 5. Nov Page 4/5

5 6.1 Rangefinder cameras Rangefinder cameras are a special model of the viewfinder cameras. Surely, the best known of such cameras are those of the Leica M series. Here, the pictures of two viewfinder windows that were independent from the main lens, were overlayed. Using the mechanics of the distance setting, those pictures began to move against each other. If only one picture of the needed object is seen, the correct distance is selected. 6.2 Tube cameras Tube cameras are also a special version of the viewfinder camera. Here, the none interchangeable lens could be moved into the camera. Often, there is a special screw mechanism to do this. But there are several other types used, too. For example on a Druopta Vega III exists a special lock. Putting the lens inside the camera reduces the overall size and helps to carry or store it easily. Abbildung 9: Tubuskamera Last changed: 5. Nov Page 5/5