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The view camera is a type of camera first developed in the era of the daguerreotype〔Stroebel, L. D. (1986). ''View Camera Technique'', 5th ed., p. 212. Boston: Focal Press. ISBN 0-240-51711-3〕 (1840s-'50s) and still in use today, though with many refinements. It comprises a flexible bellows that forms a light-tight seal between two adjustable ''standards'', one of which holds a lens, and the other a viewfinder or a photographic film holder.〔Stroebel (1986). p. 2.〕 The bellows is a flexible, accordion-pleated box. It encloses the space between the lens and film, and flexes to accommodate the movements of the standards.〔Adams, A. (1980). ''The Camera'', p. 34. Boston: Little, Brown and Company. ISBN 0-8212-1092-0〕 The ''front standard'' is a board at the front of the camera that holds the lens and, usually, a shutter. At the other end of the bellows, the ''rear standard'' is a frame that holds a ground glass, used for focusing and composing the image before exposure—and is replaced by a holder containing the light-sensitive film, plate, or image sensor for exposure. The front and rear standards can move in various ways relative to each other, unlike most other camera types. This provides control over focus, depth of field, and perspective. The camera is usually used on a tripod or other support. ==Types of view camera== Several types of view cameras are used for different purposes, and provide different degrees of movement and portability. They include: * Monorail camera - This is the most common type of studio view camera, with front and rear standards mounted to a single rail that is fixed to a camera support. This design gives the greatest range of movements and flexibility, with both front and rear standards able to tilt, shift, rise, fall, and swing in similar proportion. These are generally made of metal with leather or synthetic bellows, and are difficult to pack for travel. Sinar and Toyo are popular manufacturers of monorail view camera systems. ARCA-Swiss produces monorail cameras for field use in addition to models for the more conventional studio applications. Many manufacturers also offer monorail extensions that move the front or rear standards farther away from each other to facilitate focusing on close objects (macrophotography). * Field camera - These have the front and rear standard mounted on sliding rails fixed to a hinged flat bed that is fixed to a camera support (tripod, etc.). These cameras are usually made of wood, or sometimes lightweight and strong composites such as carbon fiber. With bellows fully retracted, the flat bed folds up, reducing the camera to a relatively small, light, and portable box. The price for this portability is that the standards are not as mobile or as adjustable as on a monorail design. The rear standard in particular may be fixed and offer no movement. These large format but transportable cameras are popular with landscape photographers. Tachihara and Wisner are examples of modern field cameras at opposite ends of the price scale. * * Extremely large field cameras use 11×14 film and larger, or panoramic film sizes such as 4×10 or 8×20. These are sometimes called ''banquet cameras'', and once were commonly used to photograph large, posed groups of people to mark occasions, such as banquets or weddings. * * ''Studio and salon cameras'' are similar to field cameras, but do not fold up for portability. * * Before the introduction of rollfilm, folding plate cameras with limited movements as described here were often used. An example is the Goerz Taro-Tenax 9x12cm.〔Picture of C.P.Goerz Taro-Tenax 9x12〕 * Press and technical cameras are true view cameras, as almost all of them have a ground glass integral to the film-holder mechanism that allows critical focus and full use of the sometimes limited movements. More expensive examples had a wide array of movements, as well as focusing and compositing aids like rangefinders and viewfinders. They are most often made of metal, designed to fold up quickly for portability, used by press photographers before and during the second world war. * A more modern development is the highly portable Sinar arTec view camera, which doesn't fit within any of the above criteria. It was designed primarily for architectural photography. It has the novel ability to take panoramic stitched images by means of a built-in step and repeat mechanism. View cameras use large format sheet film—one sheet per photograph. Standard sizes in inches are: 4×5, 5×7, 4×10, 5×12, 8×10, 11×14, 7×17, 8×20, 12×20, and 20×24. (It is usual to list the short side first in the Americas, and the long side in many other countries, thus 4×5 is the same as 5×4). A similar, but not identical, range of metric sizes is used in many countries; thus 9×12 cm is similar to, but not interchangeable with, 4×5 inches. The most widely used format is 4×5, followed by 8×10. A few rollfilm cameras have movements that make them as versatile as a sheet film view camera. Rollfilm and instant film backs are available to use in place of a sheetfilm holder on a single-film camera. ==Movements== Photographers use view cameras to control focus and convergence of parallel lines. Image control is done by moving the front and/or rear standards. Movements are the ways the front and rear standards can move to alter perspective and focus. The term can also refer to the mechanisms on the standards that control their position. Not all cameras have all movements available to both front and rear standards, and some cameras have more movements available than others. Some cameras have mechanisms that facilitate intricate movement combinations. Some limited view camera–type movements are possible with SLR cameras using various tilt/shift lenses. Also, as use of view cameras declines in favor of digital photography, these movements are simulated using computer software. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「view camera」の詳細全文を読む スポンサード リンク
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