Tagged: ½ inch

DASH (Digital Audio Stationary Head) (1982 – mid-1990s)

Sony introduced the DASH (Digital Audio Stationary Head) in 1982 for use in professional recording studios. The DASH system could record two-channel audio on ¼-inch tape, or 24 or 48 tracks onto ½-inch tape, and DASH recorders were produced by Sony, Studer and TASCAM.

The tape itself looked identical to standard NAB open reel analogue tape, but tape for use in DASH and the competing (and incompatible) ProDigi format systems used metal-particle tape which was not suitable for use in analogue systems due to the faster wear on the heads. Several companies produced open reel metal-particle tape for digital audio systems, and some examples included 3M Scotch 275, Ampex 467, EMTEC 931 and Sony own-brand tape. Metal-particle tape was even more expensive than oxide-based tape for analogue systems.

Unlike some other digital audio recording systems using tape such as DAT or U-Matic which used helical scanning, the DASH and ProDigi systems used a stationary recording head.

The audio was encoded as PCM, and included error correction, and all DASH recorders were capable of using 16-bit resolution with a 44.1 or 48 kHz sampling rate, with a couple of models capable of 24-bit 48 kHz operation.

DASH and ProDigi were the two main open-reel digital audio recording systems in use from the early-1980s to the mid-1990s, but eventually the falling price of hard-disk space, as well as more compact systems such as ADAT, made them less viable.

Although DASH was a digital system, it still had the disadvantage of having to wind through the tape to find a particular point, and wear could still be a problem. Poorly maintained machines or tape, dust, or fingerprints could render tapes unusable despite the error correction system.

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media stability 5obsolescence 5

EIAJ-2 (1972 – late 1970s)

EIAJ-2 was a video tape format developed by the Electronic Industries Association of Japan and sold by Matsushita under the National or Panasonic brands, and also by Hitachi. The format is also referred to as Omnivision. It was introduced around 1972, as Billboard magazine refers to it being under development in August 1972, and in February 1973, Panasonic re-emphasised its commitment to the format.

It was a development of the open reel EIAJ-1 standard and used the same ½-inch tape and recording specifications. However, the tape was enclosed in a cartridge to do away with the need for manually threading it, but unlike later video cassette formats the take-up reel is enclosed within the video recorder so the cartridge needed to be rewound before the cartridge could be removed from the machine.

EIAJ-2 offered colour recording on 30 minute cartridges (a 60 minute cartridge came later, and appears to be rare) and was used in the industrial, educational and consumer markets.

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media stability 5obsolescence 5

Betacam SP (1986 – 2001)

Betacam SP (Superior Performance) was an analogue broadcast video cassette format, introduced in 1986 as a improvement on the original Betacam.

It used metal-formulated tape and offered increased horizontal resolution of 340 lines. Betacam SP became the industry standard for most TV stations and high-end production houses until the late 1990s.

Betacam SP came in two sizes, with the S-size based on the original Betacam shell and intended for use in camcorders, and the new L-size intended for video editing machines. Whereas Betacam was limited to 30 minutes recording time on the S-size cassettes, the L-size Betacam SP cassette allowed for up to 90 minutes.

A digital version, Digital Betacam was launched in 1993, and subsequently, Betacam SX was launched in 1996 as a cheaper digital alternative.

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MII (1986 – early 1990s)

MII (pronounced as M 2) was an analogue videocassette format introduced by Panasonic in 1986 for professional use, to compete with Sony’s Betacam SP format.

MII was a development of the M format, which was originally derived from VHS, and it used ½ inch wide metal-formulated tape and component video recording.

Two sizes of MII cassette were available. The larger one was similar to a VHS cassette in size and had either a 60 or 90 minute recording time, and the smaller version provided 20 minutes.

MII had more success in the marketplace than its predecessor M, but MII suffered from poor marketing and customer support, and the machines gained a reputation for being less robust than those for Betacam SP.

It was used by a few UK television companies until the early 1990s, including Thames Television and TV-am. It was also used by NBC and PBS in the US, but NBC dropped it in the early 1990s in favour of the digital Sony D2 format.

The tape used in MII cassettes is very thin, and if stored badly can become mouldy and hence prone to tearing.

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media stability 3obsolescence 5

MPEG IMX (2001 – 2016)

MPEG IMX (also known as D10) was a standard-definition digital video cassette format introduced by Sony in 2001 and was part of the Betacam family of professional video formats. It was priced between Sony’s Betacam SX and the more expensive Digital Betacam, and was intended to compete with the Panasonic DVCPRO 50 system. As the name suggests, MPEG IMX recorded in MPEG video format, in case MPEG-2 using only I-frames and 8 channel audio.

Like other Betacam formats, tape width was ½ inch and cassettes were available in small or large form factors, with the S size holding up to 60 minutes of video, and the L size up to 184 minutes. To distinguish MPEG IMX tapes from other Betacam formats, the shells were coloured green. Metal particle tape was used.

All IMX video recorders could playback Betacam SX tapes, and some could playback Digital Betacam as well as analogue Betacam and Betacam SP tapes, the video from which could be encoded into MPEG-2 format. Only IMX tapes could be used for recording in IMX video recorders.

Like all Betacam formats, no new MPEG IMX video recorders are being made, having been discontinued in 2016.

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HDCAM SR (2003 – 2016)

HDCAM SR (Superior Resolution) was a professional high-definition digital video cassette format, introduced by Sony in 2003 as a higher quality variant of its existing HDCAM system.

Like other Betacam-related formats, HDCAM SR cassettes were available in large and small sizes, and had the same tape lengths as Digital Betacam (up to 40 minutes for S and 124 minutes for L tapes).

It used higher particle density tape allowing an increased bit rate (a choice or 440 or 880 Mbps). Like HDCAM, it was commonly used in high-definition television production.

Sony HDCAM SR tapes were black with a cyan lid and contained a 1K memory chip to store metadata about the tape.

In 2016, Sony announced that it was ceasing production of its remaining ½-inch video tape recorders and players, including those for the HDCAM SR format.

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ADAT (Alesis Digital Audio Tape) (1992 – 2003)

ADAT was a digital audio recording format, and was aimed at the professional studio market. It was introduced by Alesis and the first recorders were shipped in 1992.

ADAT could record up to 8 tracks, but multiple machines could be connected and synchronised to create recordings with up to 128 tracks. At the time, the only alternatives were 2 track DAT machines or very expensive digital open reel (DTRS was introduced a year later). ADAT was very sucessful, partly due to its affordability, and over 110,000 ADAT recorders were sold worldwide.

The recorder used S-VHS cassettes as the recording medium. Although intended for analogue video recording, these tapes were ideal for ADAT, with their width allowing for 8 tracks, good quality, and easy availability at the time. Although specially made S-VHS cassettes were available for the ADAT format, any premium-quality S-VHS video cassette could be used, though it was recommended to be no more than 120 minutes long (when used for ADAT, up to 40 minutes per tape was possible).

The first generation of ADAT recorders (also known as ‘Blackface’) recorded at 16 bits per sample (ADAT Type I). Later generations supported 20 bits per sample (ADAT Type II) but were backward compatible with recordings from the first generation.

ADAT was discontinued in 2003, but the name lived on in the ADAT HD24, a hard-drive based recorder.

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StorageTek 9840 (1998 – 2009)

The StorageTek 9840 was a magnetic tape system for data backup, primarily for mainframe use. The series was first introduced in 1998 with the T9840A, which had an uncompressed capacity of 20 GB. The final incarnation was the T9840D which had a capacity of 75 GB.

The StorageTek 9840 was unusual compared to its competitors such LTO and Super DLT, and to other StorageTek formats such the T10000, as the cartridges contained two reels, reducing the amount of tape that was stored in the cartridge but making loading of the tape very fast. Like many other backup tape cartridges, it used serpentine recording and ½-inch tape.

The T9840B doubled the data transfer rate of the T9840A model, making it the fastest tape drive at the time, though it was considered expensive compared to rivals, especially as its capacity was lower.

The final 9840 drives were shipped in 2009.

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VX (1975 – 1977)

VX was an early analogue video cassette format aimed at the consumer market. It was launched by Matsushita in Japan in 1975, and was also sold in the US under the Quasar brand. The only machine using the VX format in the US was the VR-1000, marketed under the name ‘The Great Time Machine’ as it could be programmed to record at specific times. In Japan, only two models of video recorder were made.

The tape in a VX cassette was ½-inch wide, and was wound on two coaxial reels (like the VCR and Cartrivision formats). The tape was pre-formed in a loop to go around the video head, which was inserted into the cassette after a protective plug was removed by the machine. The video head itself could be unscrewed and removed for cleaning or replacement.

Tape lengths of up to two hours (120 minutes, or 1200 feet) were available, but the cassettes were much larger than cassettes for the Betamax or VHS systems that pulled the tape out of the cassette to loop around the video head.

Matsushita later went on to support JVC in its introduction of VHS and by 1977 had started producing VHS video recorders.

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StorageTek T10000 / T10000 T2 (2006 – )

StorageTek T10000 is a line of magnetic tape formats for high-capacity data storage, typically used with large computer systems and often with a robotic tape library. The T10000 line was first introduced in 2006.

The first two tape drives in the line, the T10000 and T10000B, offered a capacity of 500 GB and 1 TB respectively on the same cartridge. A later version of the cartridge introduced in 2011, the T10000 T2, allowed for capacities of 5 TB and 8.5 TB in the T10000C and T10000D drives.

The T10000 is a cartridge format, containing a single-reel of ½-inch tape, similar to formats such IBM 3480 and Digital Linear Tape. The T10000 uses serpentine recording and the cartridges contain an RFID tag for information such as volume serial numbers.

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