Professional video camera

Modern digital television camera with a DIGI SUPER 86II xs lens from Canon. The camera was used during a bandy match between Hammarby and GAIS in Elitserien, Zinkendamms IP (Stockholm) 2012-02-11.

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

The 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-amplifiers and other necessary electronics, and was connected to a large diameter multicore cable to the remainder of the camera electronics, usually mounted in a separate room in the studio, or a remote truck. The camera head could not generate a video picture signal on its own. The video signal was output to 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 Camera control unit(CCU). The CCU in turn was used to align and operate the camera's functions, such as exposure, system timing, video and black levels.

This 1954 RCA TK-41C, shown here mounted on a dolly, weighed 310 lbs.

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 their 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 (the body of the camera, containing the lens and pickup tubes, 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).

A 1973 Ikegami HL-33 ENG

The Ikegami HL-33,[1] the RCA TK45[2] and the Thomson Microcam[3] 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 replaced the 16mm film cameras for TV news production from the 1970s onwards 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.

Chronology

Usage types

Most professional cameras utilize an optical prism block directly behind the lens. This prism block (a trichroic assembly comprising two dichroic prisms) separates the image into the three primary colors, red, green, and blue, directing each color into a separate charge-coupled device (CCD) or Active pixel sensor (CMOS image sensor) mounted to the face of each prism. Some high-end consumer cameras also do this, producing a higher-resolution image, with better color fidelity than is normally possible with just a single video pickup.

In both single sensor and triple sensor designs, the weak signal created by the sensors is amplified before being encoded into analog signals for use by the viewfinder and also encoded into digital signals for transmission and recording. The analog outputs were normally in the form of either a composite video signal, which combined the color and luminance information to a single output; or an R-Y B-Y Y component video output through three separate connectors.

Studio cameras

Studio camera with Teleprompter

Most television studio cameras stand on the floor, usually with pneumatic or hydraulic mechanisms called pedestals to adjust the height, and are usually on wheels. Any video camera when used along with other video cameras in a multiple-camera setup is controlled by a device known as CCU (camera control unit), to which they are connected via a Triax, Fibre Optic or the almost obsolete multicore cable. The CCU along with genlock and other equipment is installed in the production control room (PCR) often known as the Gallery of the television studio. When used outside a formal television studio in outside broadcasting (OB), they are often on tripods that may or may not have wheels (depending on the model of the tripod). Initial models used analog technology, but are now obsolete, supplanted by digital models. Studio cameras are light and small enough to be taken off the pedestal and the lens changed to a smaller size to be used on a Multiple-camera setup's shoulder. Cameras can be mounted on a tripod, a dolly or a crane, thus making the cameras much more versatile than previous generations of studio cameras. These cameras have a tally light, a small signal-lamp used that indicates, for the benefit of those being filmed as well as the camera operator, that the camera is 'live' - i.e. its signal is being used for the 'main program' at that moment.

ENG cameras

Sony camera head with Betacam SP dock recorder.

ENG (electronic news gathering) video cameras were originally designed for use by news camera operators. While they have some similarities to the smaller consumer camcorder, they differ in several regards:

EFP Cameras

EFP Camera operator at a baseball game

Electronic field production cameras are similar to studio cameras in that they are used primarily in multiple camera switched configurations, but outside the studio environment, for concerts, sports and live news coverage of special events. These versatile cameras can be carried on the shoulder, or mounted on camera pedestals and cranes, with the large, very long focal length zoom lenses made for studio camera mounting. These cameras have no recording ability on their own, and transmit their signals back to the broadcast truck through a fiber optic, triax or the virtually obsolete multicore cable.

Others

A remote-controlled camera mounted on a miniature cable car for mobility.

Remote cameras are typically very small camera heads designed to be operated by remote control. Despite their small size, they are often capable of performance close to that of the larger ENG and EFP types.

Block cameras are so called because the camera head is a small block, often smaller than the lens itself. Some block cameras are completely self-contained, while others only contain the sensor block and its pre-amps, thus requiring connection to a separate camera control unit in order to operate. All the functions of the camera can be controlled from a distance, and often there is a facility for controlling the lens focus and zoom as well. These cameras are mounted on pan and tilt heads, and may be placed in a stationary position, such as atop a pole or tower, in a corner of a broadcast booth, or behind a basketball hoop. They can also be placed on robotic dollies, at the end of camera booms and cranes, or "flown" in a cable supported harness, as shown in the illustration.

Lipstick cameras are so called because the lens and sensor block combined are similar in size and appearance to a lipstick container. These are either hard mounted in a small location, such as a race car, or on the end of a boom pole. The sensor block and lens are separated from the rest of the camera electronics by a long thin multi conductor cable. The camera settings are manipulated from this box, while the lens settings are normally set when the camera is mounted in place.

See also

References

Notes

  1. ↑ "HD Time Machine". HD Camera Guide. Retrieved 22 September 2014.
  2. ↑ "RCA TV Camera Section". The Broadcast Archive. Retrieved 22 September 2014.
  3. ↑ "Thomson TTV1602 Microcam". Museum of the Broadcast Television Camera. Retrieved 22 September 2014.
  4. ↑ link to MK IV
  5. ↑ http://www.meldrum.co.uk/mhp/knackers/cameras.html
  6. ↑ History of TV on Google Books

Bibliography

External links

Wikimedia Commons has media related to Video cameras.
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