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Media type | Magnetic cassette tape, ¾-inch |
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Encoding | NTSC, PAL, SECAM |
Developed by | Sony |
Usage | Video production |
Released | September 1971 Lifespan: September 1971–June 2000 Technical Support 1971–2016 |
U-matic or 3⁄4-inch Type E Helical Scan [1] [2] or SMPTE E [3] is an analogue recording videocassette format first shown by Sony in prototype in October 1969, and introduced to the market in September 1971. It was among the first video formats to contain the videotape inside a cassette, as opposed to the various reel-to-reel or open-reel formats of the time. The videotape is 3⁄4 in (19 mm) wide, so the format is often known as "three-quarter-inch" or simply "three-quarter", compared to open reel videotape formats in use, such as 1 in (25 mm) type C videotape and 2 in (51 mm) quadruplex videotape.
Unlike most other cassette-based tape formats, the supply and take-up reels in the cassette turn in opposite directions during playback, fast-forward, and rewind: one reel would run clockwise while the other would run counter-clockwise. A locking mechanism integral to each cassette case secures the tape hubs during transportation to keep the tape wound tightly on the hubs. Once the cassette is taken off the case, the hubs are free to spin. A spring-loaded tape cover door protects the tape from damage; when the cassette is inserted into the VCR, the door is released and is opened, enabling the VCR mechanism to spool the tape around the spinning video drum. Accidental recording is prevented by the absence of a red plastic button fitted to a hole on the bottom surface of the tape; removal of the button disabled recording.
As part of its development, in March 1970, Sony, Matsushita Electric Industrial Co. (Panasonic), Victor Co. of Japan (JVC), and five non-Japanese companies reached agreement on unified standards. The first U-matic VCRs were released by Sony in 1971. [4]
The first generation of U-matic VCRs are large devices, approximately 30 in (76 cm) wide, 24 in (61 cm) deep, and 12 in (30 cm) high, requiring special shelving, and had mechanical controls limited to Record, Play, Rewind, Fast-Forward, Stop and Pause (with muted video on early models). Later models sported improvements such as chassis sized for EIA 19-inch rack mounting, with sliding rack rails for compressed storage in broadcast environments, solenoid control mechanics, jog-shuttle knob, remote controls, Vertical Interval Time Code (VITC), longitudinal time code, internal cuts-only editing controls, "Slo-Mo" slow-motion playback, and Dolby audio noise reduction.
U-matic was named after the shape of the tape path when it was threaded around the helical-scan video head drum, which resembles the letter U. [5] Betamax uses a similar type of "B-load" as well. Recording time is limited to one hour. It initially had a resolution of 250 lines. Signals are recorded onto the tape using Frequency modulation (FM modulation).
U-matic saw two revisions to improve its image quality. The first was High-band or Hi-band, with the original version becoming known as Low-band or Lo-band. This was followed by SP (superior performance). Both revisions increased the FM carrier frequencies, increasing the available bandwidth on the tape, hence increasing image quality and the number of resolution lines. U-matic SP also introduced chrome dioxide tape. U-matic Hi-band recordings will play in black and white in U-matic Lo-band machines. [6]
PAL U-matic Hi-band increased the FM carrier frequency to 4.8-6.4 MHz, while U-matic SP increased it even further to 5.6-7.2 MHz, while increasing the color carrier frequency to 924 kHz. [7]
U-matic tape moves at 3.75 inches per second, and has a tape writing speed of 8.54 meters per second for PAL or 10.26 for NTSC. This means that the heads on the drums of U-matic VCRs move across the tape at one of those speeds. The drum has two heads, both of which are used for recording video. The drum spins at 1500 rpm for PAL or 1800 rpm for NTSC. [8] U-matic Lo-band when recording NTSC has a sync tip frequency of 3.8 MHz, a peak white frequency of 5.4 MHz, and a color carrier frequency of 688.373 kHz. NTSC U-matic SP has a peak white frequency of 7 MHz.
When recording PAL, U-matic Hi-band had a sync tip frequency of 4.8 MHz, a peak white frequency of 6.4 MHz, and a color carrier frequency of 983.803 kHz, while U-matic Hi-Band SP had a sync tip frequency of 5.6 MHz, and a peak white frequency of 7.2 MHz, retaining the color carrier frequency of regular Hi-band. [9]
Some of the standards that define the format, are: [10]
At the 1971 introduction of the first model of U-Matic VCR, the VO-1600, Sony originally intended it to be a videocassette format oriented at the consumer market, even including a VHF/UHF TV tuner built into the model for home television recording. This proved to be something of a failure, because of the high manufacturing cost and resulting retail price of the format's first VCRs. [11] But the cost was affordable enough for industrial and institutional customers, where the format was very successful for such applications as business communication and educational television. As a result, Sony shifted U-Matic's marketing to the industrial, professional, and educational sectors.
U-Matic saw even more success from the television broadcast industry in the mid-1970s, when a number of local TV stations and national TV networks used the format when its first portable model, the Sony VO-3800, was released in 1974. This model ushered in the era of ENG, or electronic news gathering, which eventually made obsolete the previous 16mm film cameras normally used for on-location television news gathering. Film required developing which took time, compared to the instantly available playback of videotape, making faster breaking news possible.
U-matic was also available in a smaller cassette size, officially known as U-Matic S. U-Matic S was developed as a more portable version of U-Matic, to be used in smaller-sized S-format recorders such as the aforementioned Sony VO-3800, as well as the later VO-4800, VO-6800, VO-8800, BVU-50, BVU-100, BVU-110, and BVU-150 models from Sony, among others from Sony, Panasonic, JVC and other manufacturers. To minimize weight and bulk in the field, portable recorders had an external AC power supply, or could be operated from rechargeable nickel-cadmium batteries. S-format tapes could be played back in older top-loading standard U-Matic decks with the aid of an adapter (the KCA-1 from Sony) which fitted around an S-sized tape; newer front-loading machines can accept S-format tapes directly, as the tapes have a slot on the underside that rides along a tab.
The standard cassette employed only one flange for each reel - top flange on the pickup reel and bottom flange on the supply reel. This allowed the reels to overlap like in Compact Cassette, making the design more space-efficient. JVC explored similar approach for an early version of VHS cassette, but abandoned it in favor of full-flanged cassette, because such an arrangement created unnecessary friction between the edge of the tape and the inner surface of the cassette. [12] In the U-Matic cassette friction was reduced by the reels, having overlapping flanges, rotating in the opposite direction. Nevertheless, the U-Matic S cassette acquired traditional double-flange reels, which reduced the amount of tape that could be loaded, and as such, the duration of recording. U-Matic S tapes had a maximum recording time of 20 minutes, and large ones 1-hour, although some tape manufacturers such as 3M came out with 30-minute S-tapes and 75-minute large cassettes (and DuPont even managed 90-minute tapes) [13] by using a thinner tape. It was the U-Matic S-format decks that ushered in the beginning of ENG, or electronic news gathering.
The price point of the VO family was primarily oriented toward educational, corporate and industrial fields, featured unbalanced audio connectors, and did not typically include SMPTE time code (although one or two companies offered after-market modification services to install longitudinal time code). The VO-3800 was largely metal, which made the unit heavy, but still technically portable. The VO-4800 had the same functionality as the VO-3800, but at a greatly reduced weight and size, by replacing many components with plastic. The VO-6800 added the improvement of a long, thin battery standard ("candy bars") that permitted storage of the batteries in a trouser pocket. Common model numbers for these batteries were NP-1, NP-1A and NP-1B. The VO-8800 was the last of the portable VO series to be produced by Sony, and featured solenoid-controlled transport.
The Sony BVU family (Broadcast Video U-matic) added longitudinal and vertical interval SMPTE time code, balanced audio XLR connectors, and heavier-duty transport features. The BVU-50 enabled recording in the field but not playback, and the BVU-100 permitted both recording and playback in the field. Portable recorders were connected to the camera with a multi-conductor cable terminated with multi-pin connectors on each end. The cable carried bi-directional audio, video, synchronisation, record on/off control, and power. Early studio and all portable U-Matic VCRs had a drawer-type mechanism which required the tape to be inserted, followed by manual closure of the drawer (a "top-loading" mechanism). Later studio VCRs accepted the cassette from a port opening and the cassette was pulled into and seated in the transport (a "front-loading" mechanism).
Some U-Matic VCRs could be controlled by external video editing controllers, such as the cuts-only Sony RM-440 for linear video editing systems. Sony and other manufacturers, such as Convergence, Calaway, and CMX Systems, produced A/B roll systems, which permitted two or more VCRs to be controlled and synchronised for video dissolves and other motion effects, integration of the character generator, audio controllers and digital video effects (DVE).
In 1976, Sony introduced the semi backwards-compatible High-band or Hi-band revision, with the introduction of the top-loading BVU-200. [14] The original version became known as Low-band or Lo-band. U-matic Hi-band had an improved colour recording system and lower noise levels. BVU gained immense popularity in ENG and location programme-making, spelling the end of 16 mm film in everyday production. By the early 1990s, Sony's 1⁄2 in (1.3 cm) Betacam SP format had all but replaced BVU outside of corporate and budget programme making. With BVU-870, Sony made a final revision to U-matic, by further improving the recording system and giving it the same "SP" suffix as Betacam. SP had a horizontal resolution of 330 lines. The BVU-800 series Y-FM carrier frequency was upped to 1.2 MHz giving it wider bandwidth. The BVU-800 series also added Dolby audio noise reduction. Sony's BVU-900 series were the last broadcast U-matic VTRs made by Sony. [15] First-generation U-matic SP and Beta-SP recordings were hard to tell apart, but despite this the writing was on the wall for U-matic, due to intrinsic problems with the format.
A recurring problem with the format was damage to the videotape caused by prolonged friction of the spinning video drum heads against a paused videocassette. The drum would rub oxide off the tape or the tape would wrinkle; when the damaged tape was played back, a horizontal line of distorted visual image would ascend in the frame, and audio would drop out. Manufacturers attempted to minimize this issue with schemes in which the tape would loosen around the spinning head or the head would stop spinning after resting in pause mode for a pre-determined period of time. [16]
The format video image also suffered from head-switching noise, a distortion of the image in which a section of video at the bottom of the video frame would be horizontally askew from the larger portion.
The format also had difficulties with reproducing the red color on the NTSC color standard, and red images would be noisier than other colors in the spectrum. For this reason, on-camera talent was discouraged from wearing red clothing that would call attention to technical shortcomings.
Copying video from one U-matic VCR to another compromised playback reliability, and levels of head-switching noise, chroma smearing, and chroma noise compounded with every generation. These issues motivated videotape editors and engineers to use work-arounds to minimise this degradation. A time-base corrector (TBC) could be used to regenerate the sync tip portion of the video signal sent to the "recording" VCR, improving playback reliability. The "dub" cable, more formally called "demodulated" (or "demod" for short), was a multi-conductor cable that circumvented a portion of the video circuitry, minimising amplification noise. [17]
For synchronisation to broadcast or post-production editing house genlock systems, U-Matic VCRs required a time base corrector (TBC). Some TBCs had a drop-out compensation (DOC) circuit which would hold lines of video in temporary digital memory to compensate for oxide drop-out or wrinkle flaws in the videotape, however the DOC circuits required several cables and expert calibration for use.
U-matic tapes were also used for easy transport of filmed scenes for dailies in the days before VHS, DVD, and portable hard drives. Several movies have surviving copies in this form. The first rough cut of Apocalypse Now , for example (the raw version of what became Apocalypse Now Redux), survived on three U-Matic cassettes. [18]
Audio quality was compromised due to the use of longitudinal audio tape heads in combination with slow tape speed. Sony eventually implemented Dolby noise reduction circuitry (using Dolby C) to improve audio fidelity.
The 2012 film No , set in 1980s Chile, used U-matic tape for filming. [19]
U-matic was also used for the storage of digital audio data. Most digital audio recordings from the 1980s were recorded on U-matic tape via a Sony PCM-1600, -1610, or -1630 PCM adaptor. These devices accepted stereo analogue audio, digitized it, and generated "pseudo video" from the bits, storing 96 bits—three stereo pairs of 16-bit samples—as bright and dark regions along each scan line. (On a monitor the "video" looked like vibrating checkerboard patterns.) This could be recorded on a U-matic recorder. This was the first system used for mastering audio compact discs in the early 1980s. The famous compact disc 44.1 kHz sampling rate was based on a best-fit calculation for PAL and monochrome NTSC video's horizontal line period and rate and U-matic's luminance bandwidth. On playback, the PCM adapter converted the light and dark regions back into bits. Glass masters for audio CDs were made via laser from the PCM-1600's digital output to a photoresist- or dye-polymer-coated disc. This method was common until the mid-1990s.
U-matic is no longer used as a mainstream television production format, but it found lasting appeal as a cheap, well specified, and hard-wearing format. The format permitted many broadcast and non-broadcast institutions to produce television programming on an accessible budget, spawning programming distribution, classroom playback, etc. At its peak popularity, U-matic recording and playback equipment was manufactured by Sony, Panasonic and JVC, with many spin-off product manufacturers, such as video edit controllers, time base correctors, video production furniture, playback monitors and carts, etc.
Many television facilities the world over still have a U-matic recorder for archive playback of material recorded in the 1970s and 1980s. For example, the US Library of Congress facility in Culpeper, Virginia, holds thousands of titles on U-matic video as a means of providing access copies and proof for copyright deposit of old television broadcasts and films.
The VHS is a standard for consumer-level analog video recording on tape cassettes, introduced in 1976 by the Victor Company of Japan (JVC). It was the dominant home video format throughout the tape media period in the late 1970s, 1980s, and 1990s.
Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal. Videotape is used in both video tape recorders (VTRs) and, more commonly, videocassette recorders (VCRs) and camcorders. Videotapes have also been used for storing scientific or medical data, such as the data produced by an electrocardiogram.
S-VHS (スーパー・ヴィエイチエス), the common initialism for Super VHS, is an improved version of the VHS standard for consumer-level video recording. Victor Company of Japan introduced S-VHS in Japan in April 1987, with their JVC-branded HR-S7000 VCR, and in certain overseas markets soon afterward. By the end of 1987, the first S-VHS VCR models from other competitors included the Hitachi VT-2700A, Mitsubishi HS-423UR, Panasonic PV-S4764, RCA VPT-695HF, and Toshiba SV-950. It has been standardized as IEC 60774-3 and IEC 60774-4.
Betamax is a consumer-level analog recording and cassette format of magnetic tape for video, commonly known as a video cassette recorder. It was developed by Sony and was released in Japan on May 10, 1975, followed by the US in November of the same year.
Helical scan is a method of recording high-frequency signals on magnetic tape, used in open-reel video tape recorders, video cassette recorders, digital audio tape recorders, and some computer tape drives.
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.
A video tape recorder (VTR) is a tape recorder designed to record and playback video and audio material from magnetic tape. The early VTRs were open-reel devices that record on individual reels of 2-inch-wide (5.08 cm) tape. They were used in television studios, serving as a replacement for motion picture film stock and making recording for television applications cheaper and quicker. Beginning in 1963, videotape machines made instant replay during televised sporting events possible. Improved formats, in which the tape was contained inside a videocassette, were introduced around 1969; the machines which play them are called videocassette recorders.
A tape head is a type of transducer used in tape recorders to convert electrical signals to magnetic fluctuations and vice versa. They can also be used to read credit/debit/gift cards because the strip of magnetic tape on the back of a credit card stores data the same way that other magnetic tapes do. Cassettes, reel-to-reel tapes, 8-tracks, VHS tapes, and even floppy disks and early hard drive disks all use the same principle of physics to store and read back information. The medium is magnetized in a pattern. It then moves at a constant speed over an electromagnet. Since the moving tape is carrying a changing magnetic field with it, it induces a varying voltage across the head. That voltage can then be amplified and connected to speakers in the case of audio, or measured and sorted into ones and zeroes in the case of digital data.
The 8mm video format refers informally to three related videocassette formats. These are the original Video8 format and its improved successor Hi8, as well as a more recent digital recording format known as Digital8. Their user base consisted mainly of amateur camcorder users, although they also saw important use in the professional television production field.
1-inch Type C Helical Scan or SMPTE C is a professional reel-to-reel analog recording helical scan videotape format co-developed and introduced by Ampex and Sony in 1976. It became the replacement in the professional video and broadcast television industries for the then-incumbent 2-inch quadruplex videotape open-reel format. Additionally, it replaced the unsuccessful type A format, also developed by Ampex, and primarily in mainland Europe, it supplemented the type B format, developed by the Fernseh division of Bosch.
A PCM adaptor is a device that encodes digital audio as video for recording on a videocassette recorder. The adapter also has the ability to decode a video signal back to digital audio for playback. This digital audio system was used for mastering early compact discs.
MII is a professional analog recording videocassette format developed by Panasonic in 1986 in competition with Sony's Betacam SP format. It was technically similar to Betacam SP, using metal-formulated tape loaded in the cassette, and utilizing component video recording.
M is the name of a professional analog videocassette format created around 1982 by Matsushita and RCA. Developed as a competitor to Sony's Betacam format, M used the same videocassette as VHS, much the same way that Betacam was designed to take advantage of cheap and readily available Betamax videocassettes,
1-inch Type A Helical Scan or SMPTE A is a reel-to-reel helical scan analog recording videotape format developed by Ampex in 1965, that was one of the first standardized reel-to-reel magnetic tape formats in the 1–inch (25 mm) width; most others of that size at that time were proprietary. It was capable of 350 lines.
1-inch Type B Helical Scan or SMPTE B is a reel-to-reel analog recording video tape format developed by the Bosch Fernseh division of Bosch in Germany in 1976. The magnetic tape format became the broadcasting standard in continental Europe, but adoption was limited in the United States and United Kingdom, where the Type C videotape format met with greater success.
IVC 2 inch Helical scan was a high-end broadcast quality helical scan analog recording VTR format developed by International Video Corporation (IVC), and introduced in 1975. Previously, IVC had made a number of 1 inch Helical VTRs. IVC saw a chance to make a VTR that would have the quality of the then-standard 2 inch Quadruplex videotape format but with the advantages of helical scan. They then developed a VTR using this technology, the IVC Model 9000.
Compact Video Cassette (CVC) was one of the first analog recording videocassette formats to use a tape smaller than its earlier predecessors of VHS and Betamax, and was developed by Funai Electronics of Japan for portable use. The first model of VCR for the format was the Model 212, introduced in 1980 by both Funai and Technicolor as they had created a joint venture to manufacture and introduce the format to the home movie market. The system, which included the VCR and a hand held video camera, was very small and lightweight for its time.
EIAJ-1 was a standard for video tape recorders (VTRs) developed by the Electronic Industries Association of Japan with the cooperation and assistance of several Japanese electronics manufacturers in 1969. It was the first standardized format for industrial/non-broadcast VTRs using a helical scan system employing open reel tape. Previously, each manufacturer of machines in this market used a different proprietary format, with differing tape speeds, scanner drum diameters, bias frequencies, tracking head placement, and so on, although most used 1/2" wide tape. As a result, video tapes recorded on one make and/or model of VTR could only be interchanged with other machines using that specific format, hampering compatibility. For example, a reel of tape recorded on a Panasonic machine would not play on a Sony machine, and vice versa. The EIAJ-1 standard ended this incompatibility, giving those manufacturers a standardized format, interchangeable with almost all VTRs subsequently brought to market around that time. The format offered black-and-white video recording and playback on 1/2″ magnetic tape on a 7″ diameter open reel, with portable units using smaller 5″ diameter reels.
VK is a helical scan analog recording videocassette format developed by Akai in the late 1970s, that is capable of recording and playing back black & white video in either EIA and CCIR systems.
A videocassette recorder (VCR) or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other AV sources and can play back the recording after rewinding. The use of a VCR to record a television program to play back at a more convenient time is commonly referred to as time shifting. VCRs can also play back prerecorded tapes, which were widely available for purchase and rental starting in the 80s and 90s, most popularly in the VHS videocassette format. Blank tapes were sold to make recordings.