This page will contain images about VHS, as they become available.VHSTop view VHS cassette with U.S. Quarter for scale Bottom view of VHS cassette with magnetic tape exposedThe Video Home System, first released in September 1976, better known by its abbreviation VHS, is a recording and playing standard for video cassette recorders (VCRs), developed by JVC (with some of its critical technology under lucrative licensing agreements with Sony) and launched in 1976. VHS officially stands for Video Home System, but it initially stood for Vertical Helical Scan, after the relative head/tape scan technique. Some early reports claim the name originally stood for Victor Helical Scan System. VHS became a standard format for consumer recording and viewing in the 1980s and 1990s after competing in a fierce format war with Sony's Betamax and, to a lesser extent, Philips' Video 2000. VHS initially offered a longer playing time than the Betamax system, and it also had the advantage of a far less complex tape transport mechanism. Early VHS machines could rewind and fast forward the tape considerably faster than a Betamax VCR since they unthreaded the tape from the playback heads before commencing any high-speed winding. Most newer VHS machines do not perform this unthreading step, as due to improved engineering, head-tape contact is no longer an impediment to fast winding. Technical detailsA VHS cassette contains a ½ inch (12.7 mm) wide magnetic tape wound between two spools, allowing it to be slowly passed over the various playback and recording heads of the video cassette recorder. The tape speed is 3.335 cm/s for NTSC, 2.339 cm/s for PAL. A cassette holds a maximum of about 430 m of tape at the lowest acceptable tape thickness, giving a maximum playing time of about 3.5 hours for NTSC and 5 hours for PAL at "standard" (SP) quality. Most cassettes have lower recording times because they use thicker tape, which helps avoid jams; careful users generally avoid the thinnest tapes. More recent machines usually allow the selection of longer recording times by lowering the tape speed: LP mode (for PAL and some NTSC machines) halves the tape speed and doubles the recording time, while EP mode (for NTSC and some newer PAL machines, aka SLP mode) drops the tape speed to one-third, for triple the recording time. Of course, these speed reductions cause corresponding reductions in video quality; also, tapes recorded at the lower speed often exhibit poor playback performance on recorders other than the one they were produced on. Because of this, commercial prerecorded tapes were almost always recorded in SP mode. An unofficial LP mode with half the standard speed exists on some NTSC machines, but is not part of the VHS standard. VHS tapes have approximately 3 MHz of video bandwidth, and a horizontal resolution of about 240 discernible lines per scanline [1]. The frequency modulation of the luminance signal makes higher resolutions impossible within the VHS standard, no matter how advanced the recorder's technology. The vertical resolution of VHS (and all other analog recording methods) is determined by the TV standard — a maximum of 486 lines are visible in NTSC and a maximum of 576 lines in PAL. The video bandwidth is achieved with a relatively low tape speed by the use of helical scan recording of a frequency modulated luminance (black and white) signal, to which a frequency-reduced "color under" chroma (hue and saturation) signal is added. In the original VHS format, audio was recorded unmodulated in a single (monaural) linear track at the upper edge of the tape, which was limited in frequency response by the tape speed. More recent hi-fi VCRs add higher-quality stereo audio tracks which are read and written by heads located on the same spinning drum that carries the video heads, frequency modulated to the unused frequency range in between the chroma and luma signals. These audio tracks take advantage of depth multiplexing: since they use lower frequencies than the video, their magnetization signals penetrate deeper into the tape. When the video signal is written by the following video head, it erases and overwrites the audio signal at the surface of the tape, but leaves the deeper portion of the signal undisturbed. The excellent sound quality of hi-fi VHS has gained it some popularity as an audio format in certain applications; in particular, ordinary home hi-fi VCRs are sometimes used by home recording enthusiasts as a handy and inexpensive medium for making high-quality stereo mixdowns and master recordings from multitrack audio tape. Of course, for backward compatibility, hi-fi VCRs still write the linear audio track during recording, and can automatically read it during playback if the hi-fi audio is not present. Some higher-end VHS and S-VHS VCRs once offered "audio dubbing" and "video dubbing" functions. These would move the tape past the heads and keep the video unchanged while recording new linear audio or keep the linear audio unchanged while recording new video, respectively. This was useful, for example, for laying a song over a previously edited-together montage of short video clips that were the same total duration as that song. Without the dubbing features, this task would've required the tape to be copied to another tape which would cause generational loss. (Due to the different ways in which linear and HiFi audio are recorded, these kinds of dubbing were not possible with the HiFi tracks). Another high-end feature was manual audio level control, which made the VHS HiFi format much more useful for high-quality audio-only recording purposes as discussed above. These advanced features are impossible to find on later-model VCRs due to the rise of digital video formats. Another linear control track, at the tape's lower edge, holds pulses that mark the beginning of every frame of video; these are used to fine-tune the tape speed during playback and to get the rotating heads exactly on their helical tracks rather than having them end up somewhere between two adjacent tracks (a feature called tracking). Since good tracking depends on the exact distance between the rotating drum and the fixed control/audio head reading the linear tracks, which usually varies by a couple of micrometers between machines due to manufacturing tolerances, most VCRs offer tracking adjustment, either manual or automatic, to correct such mismatches. The control track can additionally hold index marks. These are normally written at the beginning of each recording session, and can be found using the VCR's index search function: this will fast-wind forward or backward to the nth specified index mark, and resume playback from there. There was a time when higher-end VCRs provided functions for manually removing and adding these index marks — so that, for example, they coincide with the actual start of the program — but this feature has become hard to find in recent models. VariationsSeveral improved versions of VHS exist, most notably S-VHS, an improved analog standard, and D-VHS, which records digital video onto a VHS form factor tape. Devices have also been invented which directly connect a personal computer to VHS tape recorders for use as a data backup device. W-VHS caters for high definition video. Another variant is VHS-C (C for compact), used in some camcorders. Since VHS-C tapes are based on the same magnetic tape as full size tapes, they can be played back in standard VHS players using a mechanical adapter, without the need of any kind of signal conversion. The magnetic tape on VHS-C cassettes is wound on one main spool and uses a gear wheel to advance the tape; the wheel and spool can also be moved by hand. This development hampered the sales of the Betamax system somewhat, because the Betamax cassette geometry prevented a similar development. There is also a JVC-designed component digital professional production format known as Digital-S or (officially) D9 that uses a VHS form factor tape and essentially the same mechanical tape handling techniques as an S-VHS recorder. This format is the least expensive format to support a pre-read edit. This format is most notably used by Fox for some of its cable networks. Signal standardsVHS can record and play back all varieties of analogue television signals in existence at the time VHS was devised. However, a machine must be designed to record a given standard. Typically, a VHS machine can only handle signals of the country it was sold in. The following signal varieties exist in conventional VHS:
Since the 1990s dual- and multistandard VHS machines have become more and more common. These can handle VHS tapes of more than one standards. E.g. regular VHS machines sold in Europe nowadays can typically handle PAL, MESECAM for record and playback, plus NTSC for playback only. Dedicated multistandard machines can usually handle all standards listed, some high end model can even convert a tape from one standard to another by using a built-in standards converter. S-VHS only exists in PAL/625/25 and NTSC/525/30. S-VHS machines sold in SECAM markets record internally in PAL, and convert to/from SECAM during record/playback, respectively. Likewise, S-VHS machines for the Brazilian market record in NTSC and convert to/from PAL-M. Tape lengthsBoth NTSC and PAL/SECAM VHS cassettes are physically identical (although the signals recorded on the tape are incompatible.) However, as tape speeds differ between NTSC and PAL/SECAM, the playing time for any given cassette will vary accordingly between the systems. In order to avoid confusion, manufacturers indicate the playing time in minutes that can be expected for the market the tape is sold in:
It is perfectly possible to record and play back a blank T-XXX tape in a PAL machine or a blank E-XXX tape in an NTSC machine, but the resulting playing time will be different than indicated. It can easily be derived by multiplying with 3/2 or 2/3, respectively. For example, a T-120 tape runs for 120 minutes in NTSC-SP, but 180 minutes in PAL-SP. Conversely, an E-300 tape runs for 300 minutes in PAL-SP, but 200 minutes in NTSC-SP. VHS vs. BetamaxAs mentioned, VHS was the winner of a protracted and somewhat bitter format war during the early 1980s against Sony's Betamax format. Since Betamax was widely perceived at the time as the better format, it is often stated that VHS' eventual victory was a victory of marketing over technical excellence. In fact, however, the root causes of VHS' victory are somewhat more complex. Betamax held an early lead in the format war, offering some technical advantages, but by 1980 VHS was gaining due to its longer tape time (3 hours maximum, compared to just 60 minutes for Betamax) and JVC's less strict licensing program. The longer tape time is sometimes cited as the defining factor in the format war, as the longer VHS tapes allowed consumers to record entire programs unattended, and arguably created the entire video rental industry by providing sufficient playing time for most feature films to be distributed on a single cassette. Ultimately Betamax did manage to make up some of the difference on recording time, but this was too little, too late. Sony ultimately conceded the fight in the late '80s, bringing out a line of VHS VCRs. The format war and the "marketing over technology" claims have taken on a life of their own, and have been used as analogies in the battles of the computer industry, including Apple vs. IBM, Macintosh vs. Windows and Microsoft vs. Netscape. Other formats such as 8mm video cassettes and MiniDV have emerged since, but these formats are by no means in complete competition with VHS. As these cassettes are much more compact in design — which also means the hardware to play and record the tapes has to be more compact than VHS, and therefore more expensive — they are much more suited to portable applications such as camcorders. 8mm tapes, introduced in the early 1980s, succeeded as a format for camcorders (both in the consumer, and to an extent, professional market), as VHS and Betamax camcorders were unsuitably large and heavy in comparison. MiniDV has largely replaced 8mm tapes as the de facto camcorder standard in more recent years as it is smaller still (some MiniDV camcorders being no larger than one's hand). In addition, it offers superior audiovisual quality, and the storage of data in digital format on tape makes for improved transfer and editing. DVD and the decline of VHSThe DVD format was introduced in 1997 and has since overtaken VHS in sales and rentals. Major U.S. retailers Circuit City and Best Buy stopped selling VHS tapes in 2002 and 2003, respectively. Many films released to theaters from 2004 onwards have later been released only on DVD and not on VHS, and many other new feature films are being released solely on DVD. Moreover, most television programs released as box sets are for sale in DVD format only. Commentators predict that 2006 will be the final year of new releases on VHS, as major studios continue to phase out VHS. Despite DVD's better quality, however, VHS is still widely used in home recording of television programs, due to the large installed base and the lower cost of VHS recorders. It can also be more convenient to use VHS tapes because they can be rewritten easily, and VCRs can be easier than DVD recorders to use. However, Tivos and DVRs are the main competitors with the VHS in home recording. List of notable VHS companies
This page about VHS includes information from a Wikipedia article. Additional articles about VHS News stories about VHS External links for VHS Videos for VHS Wikis about VHS Discussion Groups about VHS Blogs about VHS Images of VHS |
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Commentators predict that 2006 will be the final year of new releases on VHS, as major studios continue to phase out VHS. The wolverine is still trapped for its fur in some parts of its range. Moreover, most television programs released as box sets are for sale in DVD format only. Wolverines, especially males, require large home ranges. Many films released to theaters from 2004 onwards have later been released only on DVD and not on VHS, and many other new feature films are being released solely on DVD. The present worldwide wolverine population is unknown, although it appears that the animal has a very low population density throughout its range, possibly as a result of illegal hunting. retailers Circuit City and Best Buy stopped selling VHS tapes in 2002 and 2003, respectively. A small number remain in the Rocky Mountain states. Major U.S. Before the widespread European settlement of North America, however, it was found as far south as California. The DVD format was introduced in 1997 and has since overtaken VHS in sales and rentals. It is currently found primarily in arctic regions such as Alaska, northern Canada, Siberia and Scandinavia. In addition, it offers superior audiovisual quality, and the storage of data in digital format on tape makes for improved transfer and editing. The young "kits" develop rapidly, becoming adult size within the first year of up to thirteen years of life. MiniDV has largely replaced 8mm tapes as the de facto camcorder standard in more recent years as it is smaller still (some MiniDV camcorders being no larger than one's hand). The young, usually three or four, are born in the spring. 8mm tapes, introduced in the early 1980s, succeeded as a format for camcorders (both in the consumer, and to an extent, professional market), as VHS and Betamax camcorders were unsuitably large and heavy in comparison. Females often will not produce young when food is not abundant. As these cassettes are much more compact in design — which also means the hardware to play and record the tapes has to be more compact than VHS, and therefore more expensive — they are much more suited to portable applications such as camcorders. Wolverines mate in the wild, but implantation in the uterus is delayed until early winter, which delays the development of the fetus. Other formats such as 8mm video cassettes and MiniDV have emerged since, but these formats are by no means in complete competition with VHS. They have been known (and been filmed) to capture kills from other predators, such as polar bears or a wolf pack. Netscape. However, because a wolverine will attack an animal caught in a trap, early trappers often tried to kill them. Windows and Microsoft vs. It is generally not aggressive towards humans, preferring to avoid human contact. IBM, Macintosh vs. Its preference for reindeer have caused it to be hunted significantly in areas depending economically on caribou herds, and its status is sometimes in danger in such regions. The format war and the "marketing over technology" claims have taken on a life of their own, and have been used as analogies in the battles of the computer industry, including Apple vs. The wolverine is both strong and ferocious and has been known to kill animals as large as moose. Sony ultimately conceded the fight in the late '80s, bringing out a line of VHS VCRs. It has also been known to give off a strong, unpleasant odor, giving rise to the use of the term "skunk bear" to describe the animal. Ultimately Betamax did manage to make up some of the difference on recording time, but this was too little, too late. It resembles a small bear with a long tail. The longer tape time is sometimes cited as the defining factor in the format war, as the longer VHS tapes allowed consumers to record entire programs unattended, and arguably created the entire video rental industry by providing sufficient playing time for most feature films to be distributed on a single cassette. The wolverine can weigh up to 30 kg (66 lb) (male), and is 70–110 cm (27–43 in) long with a 20 cm (8 in) tail. Betamax held an early lead in the format war, offering some technical advantages, but by 1980 VHS was gaining due to its longer tape time (3 hours maximum, compared to just 60 minutes for Betamax) and JVC's less strict licensing program. This makes it very resistant to frost in the cold environment where wolverines live. In fact, however, the root causes of VHS' victory are somewhat more complex. The fur is long and dense and does not retain much water. Since Betamax was widely perceived at the time as the better format, it is often stated that VHS' eventual victory was a victory of marketing over technical excellence. It has glossy brownish-black hair with strips of light brown along the sides. As mentioned, VHS was the winner of a protracted and somewhat bitter format war during the early 1980s against Sony's Betamax format. The wolverine is a stocky and muscular omnivorous (but largely carnivorous) animal. Conversely, an E-300 tape runs for 300 minutes in PAL-SP, but 200 minutes in NTSC-SP. . For example, a T-120 tape runs for 120 minutes in NTSC-SP, but 180 minutes in PAL-SP. luscus. It can easily be derived by multiplying with 3/2 or 2/3, respectively. g. It is perfectly possible to record and play back a blank T-XXX tape in a PAL machine or a blank E-XXX tape in an NTSC machine, but the resulting playing time will be different than indicated. Two subspecies are recognised, the Old World form Gulo gulo gulo and the New World form G. In order to avoid confusion, manufacturers indicate the playing time in minutes that can be expected for the market the tape is sold in:. It is the only species currently classified in the genus Gulo. Both NTSC and PAL/SECAM VHS cassettes are physically identical (although the signals recorded on the tape are incompatible.) However, as tape speeds differ between NTSC and PAL/SECAM, the playing time for any given cassette will vary accordingly between the systems. The Wolverine (Gulo gulo) is the largest terrestrial species of the Mustelidae or weasel family, and is also called the Glutton or Carcajou. Likewise, S-VHS machines for the Brazilian market record in NTSC and convert to/from PAL-M. S-VHS machines sold in SECAM markets record internally in PAL, and convert to/from SECAM during record/playback, respectively. S-VHS only exists in PAL/625/25 and NTSC/525/30. Dedicated multistandard machines can usually handle all standards listed, some high end model can even convert a tape from one standard to another by using a built-in standards converter. regular VHS machines sold in Europe nowadays can typically handle PAL, MESECAM for record and playback, plus NTSC for playback only. E.g. These can handle VHS tapes of more than one standards. Since the 1990s dual- and multistandard VHS machines have become more and more common. The following signal varieties exist in conventional VHS:. Typically, a VHS machine can only handle signals of the country it was sold in. However, a machine must be designed to record a given standard. VHS can record and play back all varieties of analogue television signals in existence at the time VHS was devised. This format is most notably used by Fox for some of its cable networks. This format is the least expensive format to support a pre-read edit. There is also a JVC-designed component digital professional production format known as Digital-S or (officially) D9 that uses a VHS form factor tape and essentially the same mechanical tape handling techniques as an S-VHS recorder. This development hampered the sales of the Betamax system somewhat, because the Betamax cassette geometry prevented a similar development. The magnetic tape on VHS-C cassettes is wound on one main spool and uses a gear wheel to advance the tape; the wheel and spool can also be moved by hand. Since VHS-C tapes are based on the same magnetic tape as full size tapes, they can be played back in standard VHS players using a mechanical adapter, without the need of any kind of signal conversion. Another variant is VHS-C (C for compact), used in some camcorders. W-VHS caters for high definition video. Devices have also been invented which directly connect a personal computer to VHS tape recorders for use as a data backup device. Several improved versions of VHS exist, most notably S-VHS, an improved analog standard, and D-VHS, which records digital video onto a VHS form factor tape. There was a time when higher-end VCRs provided functions for manually removing and adding these index marks — so that, for example, they coincide with the actual start of the program — but this feature has become hard to find in recent models. These are normally written at the beginning of each recording session, and can be found using the VCR's index search function: this will fast-wind forward or backward to the nth specified index mark, and resume playback from there. The control track can additionally hold index marks. Since good tracking depends on the exact distance between the rotating drum and the fixed control/audio head reading the linear tracks, which usually varies by a couple of micrometers between machines due to manufacturing tolerances, most VCRs offer tracking adjustment, either manual or automatic, to correct such mismatches. Another linear control track, at the tape's lower edge, holds pulses that mark the beginning of every frame of video; these are used to fine-tune the tape speed during playback and to get the rotating heads exactly on their helical tracks rather than having them end up somewhere between two adjacent tracks (a feature called tracking). These advanced features are impossible to find on later-model VCRs due to the rise of digital video formats. Another high-end feature was manual audio level control, which made the VHS HiFi format much more useful for high-quality audio-only recording purposes as discussed above. (Due to the different ways in which linear and HiFi audio are recorded, these kinds of dubbing were not possible with the HiFi tracks). Without the dubbing features, this task would've required the tape to be copied to another tape which would cause generational loss. This was useful, for example, for laying a song over a previously edited-together montage of short video clips that were the same total duration as that song. These would move the tape past the heads and keep the video unchanged while recording new linear audio or keep the linear audio unchanged while recording new video, respectively. Some higher-end VHS and S-VHS VCRs once offered "audio dubbing" and "video dubbing" functions. Of course, for backward compatibility, hi-fi VCRs still write the linear audio track during recording, and can automatically read it during playback if the hi-fi audio is not present. The excellent sound quality of hi-fi VHS has gained it some popularity as an audio format in certain applications; in particular, ordinary home hi-fi VCRs are sometimes used by home recording enthusiasts as a handy and inexpensive medium for making high-quality stereo mixdowns and master recordings from multitrack audio tape. When the video signal is written by the following video head, it erases and overwrites the audio signal at the surface of the tape, but leaves the deeper portion of the signal undisturbed. These audio tracks take advantage of depth multiplexing: since they use lower frequencies than the video, their magnetization signals penetrate deeper into the tape. More recent hi-fi VCRs add higher-quality stereo audio tracks which are read and written by heads located on the same spinning drum that carries the video heads, frequency modulated to the unused frequency range in between the chroma and luma signals. In the original VHS format, audio was recorded unmodulated in a single (monaural) linear track at the upper edge of the tape, which was limited in frequency response by the tape speed. The video bandwidth is achieved with a relatively low tape speed by the use of helical scan recording of a frequency modulated luminance (black and white) signal, to which a frequency-reduced "color under" chroma (hue and saturation) signal is added. The vertical resolution of VHS (and all other analog recording methods) is determined by the TV standard — a maximum of 486 lines are visible in NTSC and a maximum of 576 lines in PAL. The frequency modulation of the luminance signal makes higher resolutions impossible within the VHS standard, no matter how advanced the recorder's technology. VHS tapes have approximately 3 MHz of video bandwidth, and a horizontal resolution of about 240 discernible lines per scanline [1]. An unofficial LP mode with half the standard speed exists on some NTSC machines, but is not part of the VHS standard. Because of this, commercial prerecorded tapes were almost always recorded in SP mode. Of course, these speed reductions cause corresponding reductions in video quality; also, tapes recorded at the lower speed often exhibit poor playback performance on recorders other than the one they were produced on. More recent machines usually allow the selection of longer recording times by lowering the tape speed: LP mode (for PAL and some NTSC machines) halves the tape speed and doubles the recording time, while EP mode (for NTSC and some newer PAL machines, aka SLP mode) drops the tape speed to one-third, for triple the recording time. Most cassettes have lower recording times because they use thicker tape, which helps avoid jams; careful users generally avoid the thinnest tapes. A cassette holds a maximum of about 430 m of tape at the lowest acceptable tape thickness, giving a maximum playing time of about 3.5 hours for NTSC and 5 hours for PAL at "standard" (SP) quality. The tape speed is 3.335 cm/s for NTSC, 2.339 cm/s for PAL. A VHS cassette contains a ½ inch (12.7 mm) wide magnetic tape wound between two spools, allowing it to be slowly passed over the various playback and recording heads of the video cassette recorder. . Most newer VHS machines do not perform this unthreading step, as due to improved engineering, head-tape contact is no longer an impediment to fast winding. Early VHS machines could rewind and fast forward the tape considerably faster than a Betamax VCR since they unthreaded the tape from the playback heads before commencing any high-speed winding. VHS initially offered a longer playing time than the Betamax system, and it also had the advantage of a far less complex tape transport mechanism. VHS became a standard format for consumer recording and viewing in the 1980s and 1990s after competing in a fierce format war with Sony's Betamax and, to a lesser extent, Philips' Video 2000. Some early reports claim the name originally stood for Victor Helical Scan System. VHS officially stands for Video Home System, but it initially stood for Vertical Helical Scan, after the relative head/tape scan technique. The Video Home System, first released in September 1976, better known by its abbreviation VHS, is a recording and playing standard for video cassette recorders (VCRs), developed by JVC (with some of its critical technology under lucrative licensing agreements with Sony) and launched in 1976. Viz Video (1993-). Buena Vista Home Entertainment (1989-). Miramax Home Entertainment, a unit of Buena Vista Home Entertainment (1989-). New Line Home Entertainment, a TimeWarner Company (1989-). Carolco Home Video, a division of Artisan Entertainment, a Lions Gate Company (1988-1995). Orion Home Video, a Sony Pictures Entertainment Company (1988-1997). Anchor Bay Entertainment (1980s-). Hi-Tops Video, a Heron Communications Company (1985-1992). Simitar Entertainment (1980s-1990s). Touchstone Home Entertainment, a unit of the Walt Disney Company (1984-). Artisan Entertainment, a Lions Gate Company (1984-). Family Home Entertainment, a division of Artisan Entertainment, a Lions Gate Company (1982-). NBC Home Video, an NBC/Universal Company (1981-). Universal Studios Home Video, an NBC/Universal Company (1980-). Magnetic Video, the first duplicator/distributor of movies on video cassette for home use (1977-1981). Vestron Video, a division of Artisan Entertainment, a Lions Gate Company (1979-). MGM Home Entertainment, a Sony Pictures Entertainment Company (1979-). Media Home Entertainment, a Heron Communications Company (1978-1992). Warner Home Video, a TimeWarner Company (1978-). HBO Video, a TimeWarner Company (1978-). Sony Pictures Home Entertainment (1978-). Walt Disney Home Entertainment (1978-). Twentieth (20th) Century-Fox Home Entertainment, a News Corporation Company (1977-). Paramount Home Video, a Viacom Company (1976-). E-XXX indicates playing time for PAL or SECAM in SP speed. T-XXX indicates playing time for NTSC or PAL-M in SP speed. PAL-M, Brazil). PAL/525/30 (i.e. NTSC/525/30 (Most parts of North and South America, Japan, South Korea). MESECAM/625/25 (most other SECAM countries, notably Eastern Europe and Middle East). SECAM/625/25 (SECAM, French variety). PAL/625/25 (most of Western Europe, many parts of Asia and Africa). |