Betacam is a family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, Betacam singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself.
133-610: All Betacam variants from (plain) analog recording Betacam to Betacam SP and digital recording Digital Betacam (and additionally, HDCAM and HDCAM SR), use the same shape videocassettes, meaning vaults and other storage facilities do not have to be changed when upgrading to a new format. The cassettes are available in two sizes: S (short or small) and L (long or large). The Betacam camcorder can only load S magnetic tapes , while television studio sized video tape recorders (VTR) designed for video editing can play both S and L tapes. The cassette shell and case for each Betacam cassette
266-581: A low-velocity electron scanning beam , preventing the emission of secondary electrons. Not all the electrons in the scanning beam may be absorbed in the mosaic, because the stored positive charges are proportional to the integrated intensity of the scene light. The remaining electrons are then deflected back into the anode, captured by a special grid , or deflected back into an electron multiplier . Low-velocity scanning beam tubes have several advantages; there are low levels of spurious signals and high efficiency of conversion of light into signal, so that
399-414: A photocathode with an image store (target), a scanner that reads this image (an electron gun ), and a multistage electron multiplier. In the image store, light falls upon the photocathode which is a photosensitive plate at a very negative potential (approx. -600 V), and is converted into an electron image (a principle borrowed from the image dissector). This electron rain is then accelerated towards
532-483: A 90-minute tape will record 108 minutes of video in PAL . Betacam SP is able to achieve its namesake "Superior Performance" over Betacam in the fact that it uses metal-formulated tape as opposed to Betacam's ferric oxide tape. Sony designed Betacam SP to be partially forward compatible with standard Betacam, with the capability that Betacam SP tapes recorded on Betacam SP decks can be played in oxide-era Betacam VTRs (such as
665-407: A Betacam SP tape with SX recording is inserted into a Betacam SP player, no picture or sound will appear. The helical scan head drum is 81 mm in diameter. The video tracks read by the video heads in the drum, are 32 microns wide, the drum rotates at 5400 RPM for NTSC video. The video heads have a 15.25 degree azimuth . Although Betacam SX machines have gone out of production since 2008, the format
798-457: A Betacam VCR or camcorder . Another common point between Betamax and Betacam is the placement of the stereo linear audio tracks. Also, some Betacam and Betamax portables share the same batteries. (Matsushita's rival "M" and "MII" formats took a similar approach in combining the cassette from a non-professional system- in this case, VHS - with a much higher-quality recording format. However, neither enjoyed Betacam's level of success). Betacam
931-456: A Betacam deck. However, in later years Sony discouraged this practice, suggesting that the internal tape transport of Betamax cassette was not well suited to the faster tape transport of Betacam. In particular, the guide rollers tend to be noisy. Although there is a superficial similarity between Betamax and Betacam in that they use the same tape cassette, they are really quite different formats. Betamax records relatively low-resolution video using
1064-458: A UV-variant Vidicon was also used by NASA for UV duties. Vidicon tubes were popular in 1970s and 1980s, after which they were rendered obsolete by solid-state image sensors , with the charge-coupled device (CCD) and then the CMOS sensor . All vidicon and similar tubes are prone to image lag, better known as ghosting, smearing, burn-in, comet tails, luma trails and luminance blooming. Image lag
1197-482: A bitrate of 440 Mbit/s. The "SR" stands for "Superior Resolution". The increased bitrate (over HDCAM) allows HDCAM SR to capture much more of the full bandwidth of the HD-SDI signal (1920×1080). Some HDCAM SR VTRs can also use a 2× mode with an even higher bitrate of 880 Mbit/s, allowing for a 4:4:4 RGB stream at a lower compression. HDCAM SR uses the new MPEG-4 Part 2 Studio Profile for compression, and expands
1330-399: A bitrate of 90 Mbit/s plus four channels of uncompressed 48 kHz / 20 bit PCM -encoded digital audio . A fifth analog audio track is available for cueing, and a linear timecode track is also used on the tape. It was a popular digital video cassette format for broadcast television use. It uses a head drum 81 mm in diameter that rotates at 5400 RPM for NTSC video. The video heads in
1463-399: A break-through in the development of electronic imaging devices. He named the new phenomenon as charge-storage principle. (further information: Charge-storage principle ) The problem of low sensitivity to light resulting in low electrical output from transmitting or camera tubes would be solved with the introduction of charge-storage technology by Tihanyi in the beginning of 1925. His solution
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#17327728644731596-473: A charge storage plate was shielded by a pair of special grids , a negative (or slightly positive) grid lay very close to the plate, and a positive one was placed further away. The velocity and energy of the electrons in the scanning beam were reduced to zero by the decelerating electric field generated by this pair of grids, and so a low-velocity scanning beam tube was obtained. The EMI team kept working on these devices, and Lubszynski discovered in 1936 that
1729-537: A clear image could be produced if the trajectory of the low-velocity scanning beam was nearly perpendicular (orthogonal) to the charge storage plate in a neighborhood of it. The resulting device was dubbed the cathode potential stabilized Emitron, or CPS Emitron. The industrial production and commercialization of the CPS Emitron had to wait until the end of the Second World War ; it was widely used in
1862-414: A common plate by a thin layer of isolating material, so that the positive charge resulting from the secondary emission is stored in the granules. Finally, an electron beam periodically sweeps across the target, effectively scanning the stored image, discharging each granule, and producing an electronic signal like in the iconoscope. The super-Emitron was between ten and fifteen times more sensitive than
1995-529: A contract with RCA where the NDRC paid for its further development. Upon RCA's development of the more sensitive image orthicon tube in 1943, RCA entered into a production contract with the U.S. Navy , the first tubes being delivered in January 1944. RCA began production of image orthicons for civilian use in the second quarter of 1946. While the iconoscope and the intermediate orthicon used capacitance between
2128-487: A dark halo to be seen around the object; this anomaly was referred to as blooming in the broadcast industry when image orthicon tubes were in operation. Image orthicons were used extensively in the early color television cameras such as the RCA TK-40/41 , where the increased sensitivity of the tube was essential to overcome the very inefficient, beam-splitting optical system of the camera. The image orthicon tube
2261-462: A decade, aside from some specialty models that could record digital audio . Until the introduction of the BVW-200 camera, the camera and recorder configuration was a docking system. The BVW-200 was an integrated camera recorder system. It sacrificed the flexibility of a docking camera in order to lose a substantial amount of weight. Eventually, non-docking camcorders became the most popular design by
2394-571: A defining factor in the development of color TV cameras. The most widely used camera tubes in TV production were the Plumbicons and the Saticon. Compared to Saticons, Plumbicons have much higher resistance to burn-in, and comet and trailing artifacts from bright lights in the shot. Saticons though, usually have slightly higher resolution. After 1980, and the introduction of the diode-gun Plumbicon tube,
2527-706: A dissector tube employing magnetic fields to keep the electron image in focus , an element lacking in Dieckmann and Hell's design, and in the early dissector tubes built by American inventor Philo Farnsworth . Dieckmann and Hell submitted their application to the German patent office in April 1925, and a patent was issued in October 1927. Their experiments on the image dissector were announced in September 1927 issue of
2660-444: A focused beam of electrons, originally called cathode rays , is known as a cathode-ray tube (CRT). These are usually seen as display devices as used in older (i.e., non- flat panel ) television receivers and computer displays. The camera pickup tubes described in this article are also CRTs, but they display no image. In June 1908, the scientific journal Nature published a letter in which Alan Archibald Campbell-Swinton , fellow of
2793-461: A fully electronic television system was later popularized as the "Campbell-Swinton Electronic Scanning System" by Hugo Gernsback and H. Winfield Secor in the August 1915 issue of the popular magazine Electrical Experimenter and by Marcus J. Martin in the 1921 book The Electrical Transmission of Photographs . In a letter to Nature published in October 1926, Campbell-Swinton also announced
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#17327728644732926-477: A generation of hybrid recorder, allowing use of both tape and disk recording on the same deck, and high speed dubbing from one to another. This was intended to save wear on the video heads for television studio applications, as well to speed up online editing . Betacam SX also features a good shot mark (a method for qualitative decisions made in the camcorder to be utilized during the editing process) feature that allows marking of each scene for fast scanning of
3059-490: A heterodyne color recording system and only two recording heads, while Betacam uses four heads to record in component format, at a much higher linear tape speed of 10.15 cm/s (3.99606 in./s) compared with Betamax's 1.87 cm/s (0.7362205 in./s), resulting in much higher video and audio quality. A typical L-750 length Betamax cassette that yielded about 3 hours of recording time on a Betamax VCR at its B-II Speed ( NTSC ), or on PAL , only provided 30 minutes' record time on
3192-401: A high signal-to-noise ratio . They have excellent resolution compared to image orthicons, but lack the artificially sharp edges of IO tubes, which cause some of the viewing audience to perceive them as softer. CBS Labs invented the first outboard edge enhancement circuits to sharpen the edges of Plumbicon generated images. Philips received the 1966 Technology & Engineering Emmy Award for
3325-572: A legacy of Betacam and Betacam SP tapes. Some Betacam SX decks, such as the DNW-A75 or DNW-A50, can natively play and work from the analog tapes interchangeably, because they contain both analog and digital playback heads. Betacam SX uses MPEG-2 4:2:2P@ML compression, compliant with CCIR 601, in comparison with other similar systems that use 4:1:1 or 4:2:0 chroma subsampling for coding. It gives better chroma resolution and allows certain postproduction processes such as Chroma-key . This format compresses
3458-617: A multi- dynode "electron multiplier" in 1937 made Farnsworth's image dissector the first practical version of a fully electronic imaging device for television. It had very poor light sensitivity, and was therefore primarily useful only where illumination was exceptionally high (typically over 685 cd /m ). However, it was ideal for industrial applications, such as monitoring the bright interior of an industrial furnace. Due to their poor light sensitivity, image dissectors were rarely used in television broadcasting, except to scan film and other transparencies. In April 1933, Farnsworth submitted
3591-483: A multitude of small but discrete light sensitive collectors and an isolated signal plate for reading video information, the image orthicon employed direct charge readings from a continuous electronically charged collector. The resultant signal was immune to most extraneous signal crosstalk from other parts of the target, and could yield extremely detailed images. Image orthicon cameras were still being used by NASA for capturing Apollo/Saturn rockets nearing orbit, although
3724-505: A patent application also entitled Image Dissector , but which actually detailed a CRT-type camera tube. This is among the first patents to propose the use of a "low-velocity" scanning beam and RCA had to buy it in order to sell image orthicon tubes to the general public. However, Farnsworth never transmitted a clear and well focused image with such a tube. Dissectors were used only briefly for research in television systems before being replaced by different much more sensitive tubes based on
3857-695: A patent application in November 1931, and it was issued in 1935. Nevertheless, Zworykin's team was not the only engineering group working on devices that used a charge storage plate. In 1932, the EMI engineers Tedham and McGee under the supervision of Isaac Shoenberg applied for a patent for a new device they dubbed the "Emitron". A 405-line broadcasting service employing the Emitron began at studios in Alexandra Palace in 1936, and patents were issued in
3990-421: A patent application titled Television System that included a charge storage plate constructed of a thin layer of isolating material (aluminum oxide) sandwiched between a screen (300 mesh) and a colloidal deposit of photoelectric material (potassium hydride) consisting of isolated globules. The following description can be read between lines 1 and 9 in page 2: "The photoelectric material, such as potassium hydride,
4123-422: A physical texture on a phonograph record , or a fluctuation in the field strength of a magnetic recording . Analog transmission methods use analog signals to distribute audio content. These are in contrast to digital audio where an analog signal is sampled and quantized to produce a digital signal which is represented, stored and transmitted as discrete numbers . This sound technology article
Betacam - Misplaced Pages Continue
4256-863: A problem in ED Beta VCRs, since the ED Beta format uses metal-formulated tape as well. The new Betacam SP studio decks were the players: The BVW-60 and BVW-65 (the BVW-65 features Dynamic Tracking); and the Edit Recorders: the BVW-70, and the Dynamic Tracking model, the BVW-75. The BVV-5 was the Betacam SP dockable camera back, which could play back in color if its companion playback adapter
4389-718: A single coaxial cable, while e-VTR technology extends this by allowing the same data to be transported over IP by way of an Ethernet interface on the VTR itself. All IMX VTRs can natively playback Betacam SX tapes, and some, such as the MSW-M2000P/1 are capable of playing back Digital Betacam cassettes as well as analog Betacam and Betacam SP cassettes, but they can only record to their native IMX cassettes. S tapes are available with up to 60 minutes capacity, and L tapes hold up to 184 minutes. These values are for 525/60 decks, but will extend in 625/50. A 184-minute tape will record for, as
4522-473: A uniform axial magnetic field. The orthicon's performance was similar to that of the image iconoscope, but it was also unstable under sudden flashes of bright light, producing "the appearance of a large drop of water evaporating slowly over part of the scene". The image orthicon (sometimes abbreviated IO), was common in American broadcasting from 1946 until 1968. A combination of the image dissector and
4655-566: A working device was not demonstrated until some years later. An image dissector is a camera tube that creates an "electron image" of a scene from photocathode emissions (electrons) which pass through a scanning aperture to an anode , which serves as an electron detector. Among the first to design such a device were German inventors Max Dieckmann and Rudolf Hell , who had titled their 1925 patent application Lichtelektrische Bildzerlegerröhre für Fernseher ( Photoelectric Image Dissector Tube for Television ). The term may apply specifically to
4788-406: Is a stub . You can help Misplaced Pages by expanding it . Video camera tube#Plumbicon (1965) Video camera tubes are devices based on the cathode-ray tube that were used in television cameras to capture television images, prior to the introduction of charge-coupled device (CCD) image sensors in the 1980s. Several different types of tubes were in use from the early 1930s, and as late as
4921-533: Is a 2000 development of the Digital Betacam format. Digital video compression uses H.262/MPEG-2 Part 2 encoding at a higher bitrate than Betacam SX: 30 Mbit/s (6:1 compression), 40 Mbit/s (4:1 compression) or 50 Mbit/s (3.3:1 compression). Unlike most other MPEG-2 implementations, IMX uses intraframe compression. Additionally, IMX ensures that each frame has the same exact size in bytes to simplify recording onto video tape. Video recorded in
5054-421: Is a camera tube that projects an image on a special charge storage plate containing a mosaic of electrically isolated photosensitive granules separated from a common plate by a thin layer of isolating material, somewhat analogous to the human eye 's retina and its arrangement of photoreceptors . Each photosensitive granule constitutes a tiny capacitor that accumulates and stores electrical charge in response to
5187-421: Is a category of techniques used for the recording of analog signals . This enables later playback of the recorded analog audio . Analog audio recording began with mechanical systems such as the phonautograph and phonograph . Later, electronic techniques such as wire and tape recording were developed. Analog recording methods store analog signals directly in or on the media. The signal may be stored as
5320-459: Is a digital version of Betacam SP introduced in 1996, positioned as a cheaper alternative to Digital Betacam. It stores video using MPEG-2 4:2:2 Profile@ML compression , along with four channels of 48 kHz 16 bit PCM audio. All Betacam SX equipment is compatible with Betacam SP tapes. S tapes have a recording time up to 62 minutes, and L tapes up to 194 minutes. The Betacam SX system was very successful with newsgathering operations, which had
5453-453: Is a measure of brightness. The mysterious dark "orthicon halo" around bright objects in an orthicon-captured image (also known as "blooming") is based on the fact that the IO relies on the emission of photoelectrons, but very bright illumination can produce more of them locally than the device can successfully deal with. At a very bright point on a captured image, a great preponderance of electrons
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5586-399: Is a storage-type camera tube in which a charge-density pattern is formed by the imaged scene radiation on a photoconductive surface which is then scanned by a beam of low-velocity electrons . This surface is on a glass plate and is also called the target. More specifically, this glass plate is covered in a transparent, electrically conductive, indium tin oxide (ITO) layer, on top of which
5719-454: Is a video camera tube design in which the target material is a photoconductor. The vidicon was developed in 1950 at RCA by P. K. Weimer, S. V. Forgue and R. R. Goodrich as a simple alternative to the structurally and electrically complex image orthicon. While the initial photoconductor used was selenium, other targets—including silicon diode arrays—have been used. Vidicons with these targets are known as Si-vidicons or Ultricons. The vidicon
5852-498: Is an analog component video format, storing the luminance, "Y", in one track and the chrominance , on another as alternating segments of the R-Y and B-Y components performing Compressed Time Division Multiplex , or CTDM. This splitting of channels allows true broadcast quality recording with 300 lines of horizontal luminance resolution and 120 lines chrominance resolution versus 688 kHz chroma bandwidth for domestic Betamax and
5985-566: Is captured by a Vidicon for a long time and appears as a persistent outline of the image when it changes, and the outline disappears over time. Vidicons can become damaged by direct exposure to the sun which causes them to develop dark spots. Vidicons often used antimony trisulfide as the photoconductive material. They were not very successful because of image lag, which was seen in the RCA TK-42 color camera. Si-vidicons, silicon vidicons or Epicons, Vidicons using arrays of silicon diodes for
6118-568: Is colored differently depending on the format, allowing for easy visual identification. There is also a mechanical key that allows a video tape recorder to identify which format has been inserted. The format supplanted the three-quarter-inch U-Matic format, which Sony had introduced in 1971. In addition to improvements in video quality, the Betacam configuration of an integrated professional video camera /recorder led to its rapid adoption by electronic news gathering (ENG) organizations. DigiBeta,
6251-527: Is ejected from the photosensitive plate. So many may be ejected that the corresponding point on the collection mesh can no longer soak them up, and thus they fall back to nearby spots on the target instead, much as water splashes in a ring when a rock is thrown into it. Since the resultant splashed electrons do not contain sufficient energy to eject further electrons where they land, they will instead neutralize any positive charge that has been built-up in that region. Since darker images produce less positive charge on
6384-409: Is evaporated on the aluminum oxide, or other insulating medium, and treated so as to form a colloidal deposit of potassium hydride consisting of minute globules. Each globule is very active photoelectrically and constitutes, to all intents and purposes, a minute individual photoelectric cell". Its first image was transmitted in late summer of 1925, and a patent was issued in 1928. However the quality of
6517-441: Is missing. Therefore, secondary electrons are emitted from the surface of the isolating material when the electron image reaches the target, and the resulting positive charges are stored directly onto the surface of the isolated material. The original iconoscope was very noisy due to the secondary electrons released from the photoelectric mosaic of the charge storage plate when the scanning beam swept it across. An obvious solution
6650-609: Is possible. This technology was a precursor to modern microbolometer technology, and mainly used in firefighting thermal cameras. Prior to the design and construction of the Galileo probe to Jupiter , in the late 1970s to early 1980s NASA used vidicon cameras on nearly all the unmanned deep space probes equipped with the remote sensing ability. Vidicon tubes were also used aboard the first three Landsat earth imaging satellites launched in 1972, as part of each spacecraft's Return Beam Vidicon (RBV) imaging system. The Uvicon ,
6783-673: Is still used by many newsgathering operations, including Canada's CTV , Atlanta's WSB-TV , San Diego's KFMB-TV and NBC 's operations in the San Francisco Bay Area at KNTV and KSTS . Many news archives still contain SX tapes. In August 2011, Betacam SX tapes were found in Muammar Gaddafi 's underground studio in Tripoli. CNN reporter Sara Sidner commented on-air that CNN still used the same type of tapes. MPEG IMX
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#17327728644736916-458: Is visible as noticeable (usually white or colored) trails that appear after a bright object (such as a light or reflection) has moved, leaving a trail that eventually fades into the image. It cannot be avoided or eliminated, as it is inherent to the technology. To what degree the image generated by the Vidicon is affected will depend on the properties of the target material used on the Vidicon, and
7049-486: The Royal Society ( UK ), discussed how a fully electronic television system could be realized by using cathode-ray tubes (or "Braun" tubes, after their inventor, Karl Braun ) as both imaging and display devices. He noted that the "real difficulties lie in devising an efficient transmitter", and that it was possible that "no photoelectric phenomenon at present known will provide what is required". A cathode-ray tube
7182-585: The 1990s. In these tubes, an electron beam is scanned across an image of the scene to be broadcast focused on a target. This generated a current that is dependent on the brightness of the image on the target at the scan point. The size of the striking ray is tiny compared to the size of the target, allowing 480–486 horizontal scan lines per image in the NTSC format, 576 lines in PAL , and as many as 1035 lines in Hi-Vision . Any vacuum tube which operates using
7315-534: The BVV-1A), to form the BVW-1 (BVW-1A) integrated camcorder. Those decks were record-only. The only transport controls on the deck were eject and rewind. The docked camera's VTR button started and paused the tape recorder. Later the Betacam SP docking decks had full transport controls (except a record button) but tapes could not be played back except in the camera's viewfinder in black-and-white only. Sony then came out with
7448-536: The BVW-10 could not deliver. The BVW-40 enabled for the first time editing to a Betacam master, and if set up and wired correctly, true component video editing. It was also possible to do machine-to-machine editing between a BVW-10/15 and BVW-40 without an edit controller—a single serial cable between the units was all that was required to control the player from the recorder in performing simple assemble and insert editing. Additionally, there were two field models introduced,
7581-453: The BVW-15 and BVW-40 mentioned earlier), but for playback only. Betacam SP-branded tapes cannot be used for recording in consumer Betamax VCRs like oxide Betacam tapes, due to Betacam SP's metal-formulation tape causing the video heads in a Betamax deck to wear prematurely, which are made of a softer material than the heads in a standard Betacam deck. However, Betacam SP tapes can be used without
7714-524: The BVW-22, a much less expensive desktop model that could be used for viewing and logging 90-minute cassettes of both Betacam SP and oxide types, but could not be configured into an edit system and offered only composite video output. Sony followed up the SP field recorder BVW-50 that could record and play the large-size 90 minute cassettes. After this, the deck line was relatively stagnant and incredibly popular for
7847-590: The IMX format is compliant with CCIR 601 specification, with eight channels of audio and timecode track. It lacks an analog audio (cue) track as the Digital Betacam, but will read it as channel 7 if used for playback. This format has been standardized in SMPTE 365M and SMPTE 356M as "MPEG D10 Streaming". With its IMX VTRs, Sony introduced some new technologies including SDTI and e-VTR. SDTI allows for audio, video, timecode, and remote control functions to be transported by
7980-535: The Plumbicon. Targets in Plumbicons have two layers: a pure PbO layer, and a doped PbO layer. The pure PbO is an intrinsic I type semiconductor, and a layer of it is doped to create a P type PbO semiconductor, thus creating a semiconductor junction . The PbO is in crystalline form. Plumbicons were the first commercially successful version of the Vidicon. They were smaller, had lower noise, higher sensitivity and resolution, had less image lag than Vidicons, and were
8113-666: The Superikonoskop for the 1936 Berlin Olympic Games, later Heimann also produced and commercialized it from 1940 to 1955, finally the Dutch company Philips produced and commercialized the image iconoscope and multicon from 1952 until 1963, when it was replaced by the much better Plumbicon . The super-Emitron is a combination of the image dissector and the Emitron. The scene image is projected onto an efficient continuous-film semitransparent photocathode that transforms
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#17327728644738246-583: The UK until 1963, when it was replaced by the much better Plumbicon . On the other side of the Atlantic , the RCA team led by Albert Rose began working in 1935 on a low-velocity scanning beam device they came to dub the orthicon. Iams and Rose solved the problem of guiding the beam and keeping it in focus by installing specially designed deflection plates and deflection coils near the charge storage plate to provide
8379-575: The UVW-1800, a very popular editing VTR (and companion UVW-1600 edit VTP), and the non-editing UVW-1400 VTR, and UVW-1200 VTP. The UVW-100 (and later 100B) one-piece camcorder rounded out the UVW series. Betacam and Betacam SP tape cassette shells varied in color depending on the manufacturer. Many companies sold Betacam tapes, sometimes of their own manufacture, sometimes re-branded. Fuji , Maxell , Ampex / Quantegy , BASF / EMTEC and 3M were just some of
8512-707: The United Kingdom in 1934 and in the US in 1937. The iconoscope was presented to the general public at a press conference in June 1933, and two detailed technical papers were published in September and October of the same year. Unlike the Farnsworth image dissector, the Zworykin iconoscope was much more sensitive, useful with an illumination on the target between 40 and 215 lux (4–20 ft-c ). It
8645-633: The United States. Tihanyi's charge storage idea remains a basic principle in the design of imaging devices for television to the present day. In 1924, while employed by the Westinghouse Electric Corporation in Pittsburgh, Pennsylvania, Russian-born American engineer Vladimir Zworykin presented a project for a totally electronic television system to the company's general manager. In July 1925, Zworykin submitted
8778-425: The anode (the first dynode of the electron multiplier ) around the gun at a high positive voltage (approx. +1500 V). Once it exits the electron gun, its inertia makes the beam move away from the dynode towards the back side of the target. At this point the electrons lose speed and get deflected by the horizontal and vertical deflection coils, effectively scanning the target. Thanks to the axial magnetic field of
8911-455: The capacitance of the target material (known as the storage effect) as well as the resistance of the electron beam used to scan the target. The higher the capacitance of the target, the higher the charge it can hold and the longer it will take for the trail to disappear. The remmanant charges on the target eventually dissipate making the trail disappear. Vidicons can be damaged by high intensity light exposure. Image burn-in occurs when an image
9044-616: The charge-storage phenomenon like the iconoscope during the 1930s. Although camera tubes based on the idea of image dissector technology quickly and completely fell out of use in the field of television broadcasting, they continued to be used for imaging in early weather satellites and the Lunar lander, and for star attitude tracking in the Space Shuttle and the International Space Station. The optical system of
9177-416: The common name for Digital Betacam, went on to become the single most successful professional broadcast digital recording video tape format in history, but now although Betacam remains popular in the field and for archiving, new tapeless digital products have led to a phasing out of Betacam products in television studio environments since 2006. The original Betacam format was launched on August 7, 1982. It
9310-404: The detector is an electric current whose magnitude is a measure of the brightness of the corresponding area of the image. The electron image is periodically deflected horizontally and vertically (" raster scanning ") such that the entire image is read by the detector many times per second, producing an electrical signal that can be conveyed to a display device , such as a CRT monitor, to reproduce
9443-492: The drum read helical tracks 24 microns wide. Audio is also recorded on the helical tracks. The compression algorithm used by Digital Betacam is proprietary. Another key element which aided adoption was Sony's implementation of the SDI coaxial digital connection on Digital Betacam decks. Facilities could begin using digital signals on their existing coaxial wiring without having to commit to an expensive re-installation. Betacam SX
9576-435: The electron beam so it can scan the surface of the target. The beam deposits electrons on the target and when enough photons strike the target, a difference in current is produced between the two electrically conductive layers of the target, and due to a connection to an electrical resistor this difference is output as a voltage. The fluctuating voltage created in the target is coupled to a video amplifier and used to reproduce
9709-503: The far less expensive UVW series debuted. These machines were considerably simpler, somewhat lower quality, and were designed primarily to be used as companions to computer systems, for industrial video, and other low-cost, yet high-quality, uses. The UVW decks possessed very limited front panel controls, no jog and shuttle (except by use of a DSRM-10 cable remote control); and with time base corrector (TBC) control available only with an optional remote TBC controller. These were represented by
9842-471: The field recorder BVW-25, and the BVW-21 play only portable field deck. At its introduction, many insisted that Betacam remained inferior to the bulkier one-inch type C and B videotapes, the standard broadcast production formats of the late 1970s to mid-1990s. Additionally, the maximum record time for both the cameras and studio recorders was only half an hour, a severe limitation in television production. There
9975-404: The first, 100% uncompressed D1 format, although in practice, they continued to coexist for practical and economical reasons. S tapes are available with up to 40 minutes running time, and L tapes with up to 124 minutes. The Digital Betacam format records 2.34:1 DCT - compressed digital component video signal at 10-bit YUV 4:2:2 sampling in NTSC (720×486) or PAL (720×576) resolutions at
10108-472: The focusing coil , this deflection is not in a straight line, thus when the electrons reach the target they do so perpendicularly avoiding a sideways component. The target is nearly at ground potential with a small positive charge, thus when the electrons reach the target at low speed they are absorbed without ejecting more electrons. This adds negative charge to the positive charge until the region being scanned reaches some threshold negative charge, at which point
10241-428: The image dissector focuses an image onto a photocathode mounted inside a high vacuum. As light strikes the photocathode, electrons are emitted in proportion to the intensity of the light (see photoelectric effect ). The entire electron image is deflected and a scanning aperture permits only those electrons emanating from a very small area of the photocathode to be captured by the detector at any given time. The output from
10374-418: The image. The image dissector has no " charge storage " characteristic; the vast majority of electrons emitted by the photocathode are excluded by the scanning aperture, and thus wasted rather than being stored on a photo-sensitive target. The early electronic camera tubes (like the image dissector ) suffered from a very disappointing and fatal flaw: They scanned the subject and what was seen at each point
10507-428: The integrated intensity of the scene light. The target is constructed of a mosaic of electrically isolated metallic granules separated from a common plate by a thin layer of isolating material, so that the positive charge resulting from the secondary emission is stored in the capacitor formed by the metallic granule and the common plate. Finally, an electron beam periodically sweeps across the target, effectively scanning
10640-489: The label itself specifies, 220 minutes. IMX machines feature the same good shot mark function of the Betacam SX. MPEG IMX cassettes are a muted green. This format uses a helical scan head drum 80 mm in diameter. The video tracks read by the video heads in the drum, are 22 microns wide. The video heads have a 15.25 degree azimuth. 4:2:2 Chroma subsampling is used, and the drum rotates at 5400 RPM for NTSC video. Due to
10773-416: The late 1990s. Despite the format's age and its discontinuation in 2001, Betacam SP remained a common standard for standard-definition video post-production into the 2010s. The recording time is the same as for Betacam, 30 and 90 minutes for S and L, respectively. Tape speed is slightly slower in machines working in the 625/50 format, increasing tape duration by one minute for every five minutes of run time. So,
10906-452: The light striking it. An electron beam periodically sweeps across the plate, effectively scanning the stored image and discharging each capacitor in turn such that the electrical output from each capacitor is proportional to the average intensity of the light striking it between each discharge event. After Hungarian engineer Kálmán Tihanyi studied Maxwell's equations , he discovered a new hitherto unknown physical phenomenon, which led to
11039-703: The major brands to do so. Ampex , Thomson SA , BTS each sold OEM versions of some of the Sony VTRs and camcorders at various times in the 1980s and 1990s. Other than nameplates, these models were identical to the Sony models. Internal components still bore the Sony name. Digital Betacam (commonly referred to as DigiBeta , D-Beta , DBC or simply Digi ) was introduced at 18th International Television Symposium in Montreux on June 10, 1993. It supersedes both Betacam and Betacam SP, while costing significantly less than
11172-571: The mid-1990s. The final Betacam SP camcorder was the BVW-D600, which paired a digital professional video camera front section, very similar to the one on the DigiBeta DVW-700, with an integrated Betacam SP recorder. Like every other Betacam camera system, and unlike the DigiBeta DVW-700, the camera could not play back in color without the use of an outboard adapter. In 1991, the less-expensive, "Professional", PV line of Betacam SP decks
11305-549: The number of audio channels up to 12 at 48 kHz/24 bit. HDCAM SR was used commonly for HDTV television production. Some HDCAM VTRs play back older Betacam variants, for example, the Sony SRW-5500 HDCAM SR recorder, plays back and records HDCAM and HDCAM SR tapes and with optional hardware also plays and upconverts Digital Betacam tapes to HD format. Tape lengths are the same as for Digital Betacam, up to 40 minutes for S and 124 minutes for L tapes. In 24p mode
11438-502: The original Campbell-Swinton's selenium-coated plate, but much better images were obtained when the metal plate was covered with zinc sulphide or selenide, or with aluminum or zirconium oxide treated with caesium. These experiments would form the base of the future vidicon . A description of a CRT imaging device also appeared in a patent application filed by Edvard-Gustav Schoultz in France in August 1921, and published in 1922, although
11571-588: The original Emitron and iconoscope tubes and, in some cases, this ratio was considerably greater. It was used for an outside broadcast by the BBC, for the first time, on Armistice Day 1937, when the general public could watch in a television set how the King laid a wreath at the Cenotaph. This was the first time that anyone could broadcast a live street scene from cameras installed on the roof of neighboring buildings. On
11704-441: The orthicon technologies, it replaced the iconoscope in the United States, which required a great deal of light to work adequately. The image orthicon tube was developed at RCA by Albert Rose, Paul K. Weimer, and Harold B. Law. It represented a considerable advance in the television field, and after further development work, RCA created original models between 1939 and 1940. The National Defense Research Committee entered into
11837-501: The other hand, in 1934, Zworykin shared some patent rights with the German licensee company Telefunken. The image iconoscope (Superikonoskop in Germany) was produced as a result of the collaboration. This tube is essentially identical to the super-Emitron, but the target is constructed of a thin layer of isolating material placed on top of a conductive base, the mosaic of metallic granules is missing. The production and commercialization of
11970-632: The photoconductive surface is formed by depositing photoconductive material which can be applied as small squares with insulation between the squares. The photoconductor is normally an insulator but becomes partially conductive when struck by electrons. The output of the tube comes from the ITO layer. The target is kept at a positive voltage of 30 volts and the cathode in the tube is at a voltage of negative 30 volts. The cathode releases electrons which are modulated by grid G1 and accelerated by grid G2 creating an electron beam. Magnetic coils deflect, focus, and align
12103-486: The playback adapter, the VA-500, a separate portable unit that connected via a multi-pin cable and had a composite video out jack for color playback. At first color playback required the studio source deck, the BVW-10, which could not record, only play back. It was primarily designed as a feeder deck for A/B roll edit systems, usually for editing to a one-inch Type C or three-quarter-inch U-matic cassette edit master tape. There
12236-449: The popular magazine Discovery and in the May 1928 issue of the magazine Popular Radio . However, they never transmitted a clear and well focused image with such a tube. In January 1927, American inventor and television pioneer Philo T. Farnsworth applied for a patent for his Television System that included a device for "the conversion and dissecting of light". Its first moving image
12369-399: The positive mesh effectively removing electrons from the target and causing a positive charge on it in relation to the incident light in the photocathode. The result is an image painted in positive charge, with the brightest portions having the largest positive charge. A sharply focused beam of electrons (a cathode ray) is generated by the electron gun at ground potential and accelerated by
12502-421: The potential of a charge storage plate, but Lubszynski and the EMI team were the first engineers in transmitting a clear and well focused image with such a tube. Another improvement is the use of a semitransparent charge storage plate. The scene image is then projected onto the back side of the plate, while the low-velocity electron beam scans the photoelectric mosaic at the front side. This configurations allows
12635-405: The professional U-Matic formats (~30 lines resolution left-to-right) on a relatively inexpensive cassette based format. The original Betacam cassettes, loaded with ferric-oxide tape, were identical in overall design and size (15.1 × 9.5 × 2.5 cm) to consumer-grade Betamax , introduced by Sony in 1975. Betacam cassettes could be used in a Betamax VCR; likewise, a blank Betamax tape would work on
12768-446: The recorded 1440×1080 content is upsampled to 1920×1080 on playback. The recorded video bitrate is 144 Mbit/s. There are four channels of AES/EBU 20-bit/48 kHz digital audio. It was used for some of Sony's cinema-targeted CineAlta range of products (newer CineAlta devices use flash storage). HDCAM SR , introduced in 2003, uses a higher particle density tape and is capable of recording in 10 bits 4:2:2 or 4:4:4 RGB with
12901-475: The resolution of both types was so high, compared to the maximum limits of the broadcasting standard, that the Saticon's resolution advantage became moot. While broadcast cameras migrated to solid-state charge-coupled devices, Plumbicon tubes remained a staple imaging device in the medical field. High resolution Plumbicons were made for the HD-MAC standard. Since PbO is not stable in air, the deposition of PbO on
13034-561: The results of some "not very successful experiments" he had conducted with G. M. Minchin and J. C. M. Stanton. They had attempted to generate an electrical signal by projecting an image onto a selenium-coated metal plate that was simultaneously scanned by a cathode ray beam. These experiments were conducted before March 1914, when Minchin died, but they were later repeated by two different teams in 1937, by H. Miller and J. W. Strange from EMI , and by H. Iams and A. Rose from RCA . Both teams succeeded in transmitting "very faint" images with
13167-425: The runtime increases to 50 and 155 minutes, respectively. Sony branded HDCAM cassettes are black with an orange lid, and HDCAM SR cassettes black with a cyan lid. 440 Mbit/s mode is known as SQ , and 880 Mbit/s mode is known as HQ , and this mode has recently become available in studio models (e.g. SRW-5800) as well as portable models previously available. Analog recording Analog recording
13300-518: The same in the United States. The image iconoscope (Superikonoskop) became the industrial standard for public broadcasting in Europe from 1936 until 1960, when it was replaced by the vidicon and plumbicon tubes. Indeed, it was the representative of the European tradition in electronic tubes competing against the American tradition represented by the image orthicon. The German company Heimann produced
13433-440: The scanning electrons are reflected by the negative potential rather than absorbed (in this process the target recovers the electrons needed for the next scan). These reflected electrons return down the cathode-ray tube toward the first dynode of the electron multiplier surrounding the electron gun which is at high potential. The number of reflected electrons is a linear measure of the target's original positive charge, which, in turn,
13566-406: The scene being imaged, in other words it is the video output. The electrical charge produced by an image will remain in the face plate until it is scanned or until the charge dissipates. Special Vidicons can have resolutions of up to 5,000 TV lines. By using a pyroelectric material such as triglycine sulfate (TGS) as the target, a vidicon sensitive over a broad portion of the infrared spectrum
13699-416: The scene light into a light-emitted electron image, the latter is then accelerated (and focused ) via electromagnetic fields towards a target specially prepared for the emission of secondary electrons . Each individual electron from the electron image produces several secondary electrons after reaching the target, so that an amplification effect is produced, and the resulting positive charge is proportional to
13832-403: The scene light into an electron image; the latter is then accelerated towards a target specially prepared for the emission of secondary electrons . Each individual electron from the electron image produces several secondary electrons after reaching the target, so that an amplification effect is produced. The target is constructed of a mosaic of electrically isolated metallic granules separated from
13965-446: The signal output is maximum. However, there are serious problems as well, because the electron beam spreads and accelerates in a direction parallel to the target when it scans the image's borders and corners, so that it produces secondary electrons and one gets an image that is well focused in the center but blurry in the borders. Henroteau was among the first inventors to propose in 1929 the use of low-velocity electrons for stabilizing
14098-430: The stored charges. Lubszynski, Rodda, and McGee realized that the best solution was to separate the photo-emission function from the charge storage one, and so communicated their results to Zworykin. The new video camera tube developed by Lubszynski, Rodda and McGee in 1934 was dubbed "the super-Emitron". This tube is a combination of the image dissector and the Emitron. It has an efficient photocathode that transforms
14231-429: The stored image and discharging each capacitor in turn such that the electrical output from each capacitor is proportional to the average intensity of the scene light between each discharge event (as in the iconoscope). The image iconoscope is essentially identical to the super-Emitron, but the target is constructed of a thin layer of isolating material placed on top of a conductive base, the mosaic of metallic granules
14364-473: The super-Emitron and image iconoscope in Europe were not affected by the patent war between Zworykin and Farnsworth, because Dieckmann and Hell had priority in Germany for the invention of the image dissector, having submitted a patent application for their Lichtelektrische Bildzerlegerröhre für Fernseher ( Photoelectric Image Dissector Tube for Television ) in Germany in 1925, two years before Farnsworth did
14497-405: The supervision of Isaac Shoenberg analyzed how the Emitron (or iconoscope) produces an electronic signal and concluded that its real efficiency was only about 5% of the theoretical maximum. This is because secondary electrons released from the mosaic of the charge storage plate when the scanning beam sweeps across it may be attracted back to the positively charged mosaic, thus neutralizing many of
14630-518: The tape, looking at recorded marks on each single cassette, and showing the markers to the operator. The cameras themselves are generally considered by most sound recordists to be quite noisy in operation, possibly because the amount of computer processing power, and subsequent generated heat leads to cooling fans being used to keep the camera at a reasonable temperature. Betacam SX tape shells are bright yellow, but SX recordings may also be found recorded on analogue Betacam SP cassettes. Of course if such
14763-586: The target (a very thin glass plate acting as a semi-isolator) at ground potential (0 V), and passes through a very fine wire mesh (nearly 200 or 390 wires per cm), very near (a few hundredths of a cm) and parallel to the target, acting as a screen grid at a slightly positive voltage (approx +2 V). Once the image electrons reach the target, they cause a splash of electrons by the effect of secondary emission . On average, each image electron ejects several splash electrons (thus adding amplification by secondary emission), and these excess electrons are soaked up by
14896-504: The target that produced large amounts of electrons when struck by photons, and the electrons were accelerated to the target with several hundred volts. These tubes were used for tracking satellite debris. Plumbicon is a registered trademark of Philips from 1963, for its lead(II) oxide (PbO) target vidicons. It was demonstrated in 1965 at the NAB Show . Used frequently in broadcast camera applications, these tubes have low output, but
15029-627: The target, the excess electrons deposited by the splash will be read as a dark region by the scanning electron beam. This effect was actually cultivated by tube manufacturers to a certain extent, as a small, carefully controlled amount of the dark halo has the effect of crispening the visual image due to the contrast effect . (That is, giving the illusion of being more sharply focused than it actually is). The later vidicon tube and its descendants (see below) do not exhibit this effect, and so could not be used for broadcast purposes until special detail correction circuitry could be developed. A vidicon tube
15162-651: The target, were introduced in 1969 for the Picturephone . They are very resistant to burn-in, have low image lag and very high sensitivity but are not considered suitable for broadcast TV production as they suffer from high image blooming and image non uniformity. The targets in these tubes are made on silicon substrates and require 10 volts to operate, they are made with semiconductor device fabrication processes. These tubes could be used with an image intensifier in which case they were known as silicon intensified tubes (SITs) which had an additional photocathode in front of
15295-423: The television networks had phased the cameras out. An image orthicon camera can take television pictures by candlelight because of the more ordered light-sensitive area and the presence of an electron multiplier at the base of the tube, which operated as a high-efficiency amplifier. It also has a logarithmic light sensitivity curve similar to the human eye . However, it tends to flare in bright light, causing
15428-441: The transmitted image failed to impress H.P. Davis, the general manager of Westinghouse , and Zworykin was asked "to work on something useful". A patent for a television system was also filed by Zworykin in 1923, but this filing is not a definitive reference because extensive revisions were done before a patent was issued fifteen years later and the file itself was divided into two patents in 1931. The first practical iconoscope
15561-489: The use of a straight camera tube, because the scene to be transmitted, the charge storage plate, and the electron gun can be aligned one after the other. The first fully functional low-velocity scanning beam tube, the CPS Emitron, was invented and demonstrated by the EMI team under the supervision of Sir Isaac Shoenberg . In 1934, the EMI engineers Blumlein and McGee filed for patents for television transmitting systems where
15694-550: The use of an MPEG format, video is recorded with 8-bit samples (8-bit color). The XDCAM format, unveiled in 2003, allows recording of MPEG IMX video in MXF container onto Professional Disc . HDCAM , introduced in 1997, was the first HD format available in Betacam form-factor, using an 8-bit DCT compressed 3:1:1 recording, in 1080i -compatible downsampled resolution of 1440×1080, and adding 24p and 23.976 PsF modes to later models. The HDCAM codec uses non-square pixels and as such
15827-410: The video signal from approximately 180 Mbit/s to only 18 Mbit/s. This means a compression ratio of around 10:1, which is achieved by the use of mild temporal compression, where alternate frames are stored as MPEG I-frames and B-frames, giving rise to an IBIB sequence on tape. Due to the low bitrate this format was not standardized by any standards body. Together with Betacam SX, Sony introduced
15960-598: Was a camera tube that accumulated and stored electrical charges ( photoelectrons ) within the tube throughout each scanning cycle. The device was first described in a patent application he filed in Hungary in March 1926 for a television system he dubbed Radioskop. After further refinements included in a 1928 patent application, Tihanyi's patent was declared void in Great Britain in 1930, and so he applied for patents in
16093-453: Was also easier to manufacture and produced a very clear image. The iconoscope was the primary camera tube used by RCA broadcasting from 1936 until 1946, when it was replaced by the image orthicon tube. The original iconoscope was noisy, had a high ratio of interference to signal, and ultimately gave disappointing results, especially when compared to the high definition mechanical scanning systems then becoming available. The EMI team under
16226-610: Was also the BVW-20 field playback deck, which was a portable unit with DC power and a handle, that was used to verify color playback of tapes in the field. Unlike the BVW-10, it did not have a built in time base corrector (TBC). With the popular success of the Betacam system as a news acquisition format, the line was soon extended to include the BVW-15 studio player, and the BVW-40 studio edit recorder. The BVW-15 added dynamic tracking, which enabled clear still frame and jog playback, something
16359-435: Was also the limitation that high-quality recording was only possible if the original component signals were available, as they were in a Betacam camcorder. If the recording started as composite video , re-converting them to components for recording and then eventually back to composite for broadcast caused a drop in quality compared to recording component video directly. In 1987, Betacam SP (commonly referred to as Beta SP )
16492-459: Was at one point colloquially referred to as an Immy. Harry Lubcke , the then-President of the Academy of Television Arts & Sciences , decided to have their award named after this nickname. Since the statuette was female, it was feminized into Emmy . The Image orthicon was used until the end of black and white television production in the 1960s. An image orthicon consists of three parts:
16625-476: Was constructed in 1931 by Sanford Essig, when he accidentally left a silvered mica sheet in the oven too long. Upon examination with a microscope, he noticed that the silver layer had broken up into a myriad of tiny isolated silver globules. He also noticed that, "the tiny dimension of the silver droplets would enhance the image resolution of the iconoscope by a quantum leap". As head of television development at Radio Corporation of America (RCA) , Zworykin submitted
16758-617: Was initially introduced as a camera line along with a video cassette player. The first cameras were the BVP-3, which utilized three Saticon tubes, the BVP-30, which utilized three Plumbicon tubes, and the BVP-1, which used a single tri-stripe SMF (Saticon Mixed Field) Trinicon tube. These three cameras could be operated standalone, or with their docking companion VTR, the BVV-1 (quickly superseded by
16891-502: Was introduced. The PV line consisted of only four models: the full-sized PVW-2600 (VTP), PVW-2650 (VTP with Dynamic tracking allowing up to fwd x3, whereas the BVW line only offered x2 DT playback) and PVW-2800 (VTR) editing decks, and the PVV-3 camera-dockable VTR. These high quality machines were similar to the original BV series machines, but lacked the third and fourth audio channels. In 1993,
17024-466: Was only the tiny piece of light viewed at the instant that the scanning system passed over it. A practical functional camera tube needed a different technological approach, which later became known as Charge - Storage camera tube. It was based on a new physical phenomenon which was discovered and patented in Hungary in 1926, but became widely understood and recognised only from around 1930. An iconoscope
17157-512: Was released. It increased horizontal resolution to 340 lines. While the quality improvement of the format itself was minor, the improvement to the VTRs was enormous, particularly in quality and features. In addition to the existing cassette a larger cassette (25.3 × 14.4 × 2.5 cm) was introduced with 90 minutes of recording time. Betacam SP (for "Superior Performance") became the industry standard for most TV stations and high-end production houses until
17290-577: Was successfully demonstrated as a displaying device by the German Professor Max Dieckmann in 1906; his experimental results were published by the journal Scientific American in 1909. Campbell-Swinton later expanded on his vision in a presidential address given to the Röntgen Society in November 1911. The photoelectric screen in the proposed transmitting device was a mosaic of isolated rubidium cubes. His concept for
17423-431: Was successfully transmitted on September 7 of 1927, and a patent was issued in 1930. Farnsworth quickly made improvements to the device, among them introducing an electron multiplier made of nickel and using a "longitudinal magnetic field" in order to sharply focus the electron image . The improved device was demonstrated to the press in early September 1928. The introduction of a multipactor in October 1933 and
17556-421: Was to scan the mosaic with a low-velocity electron beam which produced less energy in the neighborhood of the plate such that no secondary electrons were emitted at all. That is, an image is projected onto the photoelectric mosaic of a charge storage plate, so that positive charges are produced and stored there due to photo-emission and capacitance , respectively. These stored charges are then gently discharged by
17689-456: Was used. A new SP field recorder, the BVW-35, possessed the added benefit of a standard RS422 serial control port that enabled it to be used as an edit feeder deck. Though the four new studio decks could utilize the full 90-minute Betacam SP cassettes, the BVW-35 remained limited to the original Betacam small 30-minute cassette shells. Answering a need for a basic office player, Sony also introduced
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