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A professional video camera (often called a television camera even though the use has spread beyond television) is a high-end device for creating electronic moving images (as opposed to a movie camera, that earlier recorded the images on film). Originally developed for use in television studios, they are now also used for music videos, direct-to-video movies, corporate and educational videos, marriage videos etc. Since the 2010s, most of the professional video cameras are digital professional video cameras. With the advent of digital video capture in the 2000s, the distinction between professional video cameras and movie cameras disappeared as the intermittent mechanism became the same. Nowadays, mid-range cameras exclusively used for television and other works (except movies) are termed as professional video cameras. ==History== Earliest video cameras were mechanical flying-spot scanners which were in use in the 1920s and 1930s during the period of mechanical television. Improvements in video camera tubes in the 1930s ushered in the era of electronic television. Earlier, cameras were very large devices, almost always in two sections. The camera section held the lens and tube pre-amps and other necessary electronics, and was connected with a large diameter multicore cable to the rest of the camera electronics, usually mounted in a rack. The rack would be in a separate room in the studio, or in a remote truck. The camera head could not generate a video picture signal on its own. The video signal was output from the rack unit to the rest of the studio for switching and transmission. By the fifties, electronic miniaturization had progressed to the point where some monochrome cameras could operate stand alone and even be handheld. But the studio configuration remained, with the large cable bundle transmitting the signals back to the CCU (Camera control unit). The CCU in turn was used to align and operate the camera's functions, such as exposure, system timing, and video and black levels. The first color cameras (1950s in the US, early 1960s in Europe), notably the RCA TK-40/41 series, were much more complex with their three (and in some models four) pickup tubes, and the size and weight drastically increased. Handheld color cameras did not come into general use until the early 1970s - the first generation of cameras were split into a camera head unit (where the body of the camera, containing the lens and pickup tubes was, and held on the shoulder or a body brace in front of the operator) connected via a cable bundle to a backpack CCU (Camera Control Unit). The Ikegami HL-33,〔(【引用サイトリンク】url=http://www.hdcameraguide.com/guide/time_machine/time-machine-eng )〕 the RCA TK45〔(【引用サイトリンク】url=http://www.oldradio.com/archives/hardware/TV/RCA-TV.htm )〕 and the Thomson Microcam〔(【引用サイトリンク】url=http://www.tvcameramuseum.org/thomson/ttv1602/ttv1602p1.htm )〕 were portable two piece color cameras introduced in the early 1970s. For field work a separate VTR was still required to record the camera's video output. Typically this was either a portable 1" reel to reel VTR, or a portable 3/4" U-matic VCR. Typically, the two camera units would be carried by the camera operator, while a tape operator would carry the portable recorder. With the introduction of the RCA TK76 in 1976, camera operators were finally able to carry on their shoulders a one piece camera containing all the electronics to output a broadcast quality composite video signal. A separate videotape recording unit was still required. Electronic news-gathering (ENG) cameras rapidly replaced the 16mm film cameras for TV news production around 1940s because the cost of shooting on film was significantly more than shooting on a reusable tape. Portable video tape production also enabled much faster turnaround time for the quick completion of news stories, compared to the need to chemically process film before it could be shown or edited. However some news feature stories for weekly news magazine shows continued to use 16mm film cameras until the 1990s. At first all these cameras used tube based sensors, but CCD imagers came on the scene in the mid-80s, bringing numerous benefits. Early CCD cameras could not match the colour or resolution of their tube counterparts, but the benefits of CCD technology, such as introducing smaller and lightweight cameras, a better and more stable image (that was not prone to image burn in or lag) and no need for calibration meant development on CCD imagers quickly took off and, once rivaling and offering a superior image to a tube sensor, began displacing tube-based cameras - the latter of which were all but disused by the early 1990s. Eventually, cameras with the recorder permanently mated to the camera head became the norm for ENG. In studio cameras, the camera electronics shrank, and CCD imagers replaced the pickup tubes. The thick multi-core cables connecting the camera head to the CCU were replaced in the late seventies with triax connections, a slender video cable that carried multiple video signals, intercom audio, and control circuits, and could be run for a mile or more. As the camera innards shrunk, the electronics no longer dictated the size of the enclosure, however the box shape remained, as it is necessary to hold the large studio lenses, teleprompters, electronic viewfinder (EVF), and other paraphernalia needed for studio and sports production. Electronic Field Production cameras were often mounted in studio configurations inside a mounting cage. This cage supported the additional studio accessories. In the late 1990s, as HDTV broadcasting commenced, HDTV cameras suitable for news and general purpose work were introduced. Though they delivered much better image quality, their overall operation was identical to their standard definition predecessors. New methods of recording for cameras were introduced to supplant video tape, tapeless cameras. Ikegami and Avid introduced EditCam in 1996, based on interchangeable hard drives. Panasonic introduced P2 cameras. These recorded a DVCPro signal on interchangeable flash memory media. Several other data storage device recording systems were introduced, notably XDCAM from Sony. Sony also introduced SxS (S-by-S), a flash memory standard compliant to the Sony and Sandisk-created ExpressCard standard. Eventually flash storage largely supplanted other forms of recording media. In 2000s, major manufacturers like Sony, Philips introduced the digital professional video cameras. These cameras used CCD sensors and recorded video digitally on flash storage. These were followed by digital HDTV cameras. As digital technology improved and also due to digital television transition, digital professional video cameras have become dominant in television studios, ENG, EFP and even in other areas since 2010s. 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「professional video camera」の詳細全文を読む スポンサード リンク
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