Tagged: helical scan

1-inch Type B (1975 – 1980s)

1-inch Type B (also known as B-Format) was an open reel magnetic tape format for professional analogue video recording.

It was introduced by Bosch in 1976 for use in its BCN line of video recorders and although it found success in continental Europe, 1-inch Type C was more successful in the UK and US. Unlike Type C, Type B in its standard form could not perform trick-play operations such as slow-motion or frame step play, due to the way the each field was segmented over 5 or 6 tracks (Type C recorded one frame per helical scan). An expensive digital framestore was needed to perform trick-play operations.

Type B had a standard capacity of 96 minutes on a reel, although later this was increased to 120 minutes. Long play versions eventually became available that could fit up to 6 hours on one reel.

Video quality was excellent, and as well as standard recording/playback machines, portable and random access cart machines were available.

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Preservation / Migration

media stability 5obsolescence 5

DTRS (Digital Tape Recording System) (1993 – 2012)

DTRS (Digital Tape Recording System) was a magnetic tape format for professional digital audio recording. It was introduced by TASCAM in 1993 for use in the DA-88 digital multitrack recorder.

The DA-88 and later models could record up to eight tracks, but devices could be combined to record 16, 24 or more tracks. The first models in the range recorded at 16-bit resolution, with later models recording at 24-bit resolution. Sony also produced a DTRS recorder.

The tape itself was simply Hi8 video tape (an analogue video format) that was used to store audio in the digital DTRS format, and it allowed long continuous recording times. The format was considered to be affordable and reliable.

DTRS was discontinued in 2012, as recording studios have moved to hard-drive recording.

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Ampex 2-inch helical scan video tape (1961 – 1970)

A range of video tape recorders using helical scan technology was introduced in 1961 by Ampex, and used 2-inch wide tape like the Quadruplex system.

The video tape recorders could record black and white analogue video using non-segmented helical scanning. This differed from the Quadruplex system, as the longer stripes contained an entire television field, whereas in Quadruplex the field was broken between the 16 stripes recorded across the tape. This allowed for features such as pausing a still frame. Two audio tracks were recorded on the top edge of the tape, with a control track recorded on the tape’s bottom edge.

Ampex 2-inch helical scan video tape recorders were mostly used in industry, education, and a few for in-flight entertainment.

Tape speed was 3.7 inches per second allowing up to five hours recording time on the largest reel (containing 5540 feet of tape). Reel were available in 6½-inch, 8-inch, 10½-inch and 12½-inch sizes, and used a large NAB (National Association of Broadcasters) centre hole.

One model, the VR-660, was used by NASA to record slow-scan video from Apollo 11, and also used by the United States Air Force to record bombing runs during the Vietnam War.

Ampex ceased manufacture of 2-inch helical scan video tape recorders in 1970.

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Preservation / Migration Urgency

media stability 5obsolescence 5

Mammoth / Mammoth-2 (1994 – 2001)

Mammoth was a higher-capacity version of 8mm or Data8 tape and was introduced in 1994 by Exabyte. Mammoth-2 was subsequently introduced in 1999.

When introduced, a Mammoth tape could hold 20 GB of data.

Mammoth cassettes used Advanced Metal Evaporated (AME) tape. Although they read (but not write) earlier Exabyte 8mm tapes which used metal particle tape, it was required that Mammoth drives be cleaned after every time these were used. Mammoth-2 used tape called ‘AME with SmartClean’. Although Mammoth tapes could be used, it was not recommended.

Mammoth-2 could hold 30 GB of data.

In 2001, Exabyte merged with Ecrix, makers of VXA, and Exabyte moved away from Mammoth.

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U-matic S (1974 – 1990s)

U-matic S (for ‘Small’) was a smaller size of U-matic video tape cassette, introduced in 1974 for use in compact recording decks by television news crews.

Early top-load U-matic decks accept the smaller cassettes only with the aid of an adapter. Later, front-load decks can accept S-format tapes directly, as the tapes have a slot on the underside that rides along a tab. U-matic S tapes generally had recording times of no more than 20 minutes, though 30-minute S tapes were also available using thinner tape.

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Sony EV 1-inch open reel video tape (1964 – early 1970s)

Sony EV 1-inch video tape was introduced in 1964 with the release of the EV-200 ‘portable’ video recorder (portable meaning it had carrying handles, but it was still very heavy to carry). Most machines found their way into the educational and industrial marketplaces.

The EV-200 was monochrome, but later models could record and play in colour. Tapes are interchangeable between the models in the series.

The machines use a two head helical scanning system in a half wrap around the drum. Maximum recording time was 1 hour with 2400 ft of tape on an 8 inch reel. Tape speed was 7.8 ips. Unlike other 1-inch video tape formats, the Sony EV reels did not use NAB style hubs, but rather a straight spindle design.

The last model to use 1-inch EV tape was the Sony UV-340 of 1970.

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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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Preservation / Migration

Betacam (1982 – 1990s)


Betacam was a ½-inch analogue video cassette format for broadcast use, first introduced by Sony in 1982. As the name implies, the format was a professional version of Betamax and was rapidly adopted for electronic news gathering, replacing the Sony U-Matic ¾-inch format. Whereas Betamax lost out to VHS in consumer video, Betacam and its successors were very successful in broadcasting.

Betacam was a component video format using ferric-oxide tape and offering broadcast-quality 300-line horizontal resolution. It came in a shell the same size as Sony’s Betamax format and whilst it was possible for the two formats to use each other’s tapes, this practice was discouraged.

In 1986, Betcam SP was launched, offering a larger sized cassette for video editing, and increased resolution using metal-formulated tape.

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D1 (1987 – 1990s)

Sony’s D1 was the first digital videotape format, introduced in 1987.

D1 stores uncompressed digitised component video, with very high picture quality and was most popular in high-end graphic and animation production despite being very expensive. It uses ¾-inch tape, with a maximum record time of 94 minutes.

Sony’s Digital Betacam format, introduced in 1993, also used component video and became the defacto standard-definition broadcast format due to its affordability. But even after Digital Betacam was wide spread, the pure component, uncompressed nature of D1 was specified by major studios and commercial producers as the format of choice until HD took effect.

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8mm / Data8 (1987 – late 1990s)

8 mmThe use of 8mm magnetic tape for data storage was pioneered by Exabyte, and used the same form factor as 8mm tape for video recording (Video8). It is also referred to as Data8 or D8.

It was the first tape format for data storage to use helical-scan technology when introduced in 1987.

Later higher-capacity versions were called Mammoth and Mammoth-2 and used Advanced Metal Evaporated tape.

AIT and VXA formats also use 8mm tape but are incompatible.

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