Betamax
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| Betamax | |
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| Media type | Video recording media |
|---|---|
| Encoding | Magnetic tape |
| Developed by | Sony |
| Usage | Video storage |
Sony's Betamax is the 1/2 inch (12.7 millimeter) home videocassette tape recording format introduced on April 16, 1975 (in market on May 10) and derived from the earlier, professional 3/4 inch (19.05 millimeter) U-matic video cassette format. Like the video home recording system VHS introduced by JVC in 1976, it had no guard band, and used azimuth recording to reduce cross-talk. The "Betamax" name came from a double meaning: beta being the Japanese word used to describe the way signals were recorded onto the tape, and from the fact that when the tape ran through the transport it looked like the Greek letter "Beta" (β). The suffix -max came from "maximum" to suggest greatness.[1]
Sanyo marketed a version as Betacord, but this was also referred to casually as "Beta." In addition to Sony and Sanyo, Beta format video recorders were also sold by Toshiba, Pioneer, Aiwa and NEC, and the Zenith Electronics Corporation and WEGA Corporations contracted with Sony to produce VCRs for their product lines. Department stores like Sears, in the US and Canada, and Quelle in Germany sold Beta format VCRs under their house brands as did the RadioShack chain of electronic stores.
Betamax and VHS competed in a fierce format war which saw VHS come out on top in most markets.
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[edit] Camcorders
Sony used the Beta format to produce a one-piece camcorder for consumers - the Betamovie. (The first camcorder ever sold was a professional unit using the Betacam standard, not Betamax.) While the idea was well received, the camcorder itself was rather large, and lacked features common to two-piece camera-recorder units: It could not play back or rewind its own tape, and had an optical, rather than electronic viewfinder. In effect the camcorder operated similar to the 8mm film-based cameras of the day.
VHS manufacturers countered with the VHS-C format, and Sony eventually introduced the Video-8 format to compete with the VHS-Compact format. For more information, see the article on camcorders.
[edit] The legacy of Betamax
The VHS format's defeat of the Betamax format became a classic marketing case study. Sony's attempt to dictate an industry standard backfired when JVC made the tactical decision to forgo Sony's offer of Betamax in favor of developing their own technology. They felt that it would end up like the U-Matic deal, with Sony dominating.
By 1980, JVC's VHS format controlled 70% of the North American market. The large economy of scale allowed VHS units to be introduced to the European market at a far lower cost than the rarer Betamax units. In the UK, Betamax held a 25% market share in 1981, but by 1986 it was down to 7.5% and continued to decline further. By 1984, forty companies utilized the VHS format in comparison with Beta's twelve. Sony finally conceded defeat in 1988 when it too began producing VHS recorders.
In Japan, Betamax had more success and eventually evolved into Enhanced Definition Betamax with 500+ lines resolution, but eventually both Betamax and VHS were supplanted by laser-based technology. The last Sony Betamax was produced in 2002.
For more information on why Betamax lost to VHS, see The Videotape Format War.
[edit] Home and professional recording
One other major consequence of the Betamax technology's introduction to the U.S. was the lawsuit Sony Corp. v. Universal City Studios (1984, the "Betamax case"), with the U.S. Supreme Court determining home videotaping to be legal in the United States, wherein home videotape cassette recorders were a legal technology since they had substantial non-infringing uses. This precedent was later invoked in MGM v. Grokster (2005), where the high court agreed that the same "substantial non-infringing uses" standard applies to authors and vendors of peer-to-peer file sharing software (notably excepting those who "actively induce" copyright infringement through "purposeful, culpable expression and conduct").
In the professional and broadcast video industry, Sony's Betacam, derived from Betamax as a professional format, became one of several standard formats; production houses exchange footage on Betacam videocassettes, and the Betacam system became the most widely used videotape format in the ENG (Electronic News Gathering) industry, replacing the 3/4" U-matic tape format (which was the first practical and cost-effective portable videotape format for broadcast television, signaling the end of 16 mm film — and the phrase "film at 11" often heard on the six-o-clock newscast, before the film had been developed). The professional derivative of VHS, MII (aka Recam), faced off against Betacam and lost. Once Betacam became the de facto standard of the broadcast industry, its position in the professional market mirrored VHS's dominance in the home-video market. On a technical level, Betacam and Betamax are similar in that both share the same videocassette shape, use the same oxide tape formulation with the same coercivity, and both record linear audio tracks on the same location of the videotape. But in the key area of video recording, Betacam and Betamax are completely different. BetaCam tapes are mechanically interchangeable with Betamax, but not electronically. BetaCam moves the tape at 12 cm/sec, with different recording/encoding techniques. Betamax is a color-under system with linear tape speeds ranging from 4 cm/sec to 1.33 cm/sec.
Sony also offered a range of Industrial Betamax products, a Beta I only format for industrial and institutional users. Basically cheaper and smaller than U-Matic. The arrival of the Betacam system reduced the demand for both Industrial Beta and U-Matic equipment.
Betamax also had a significant part to play in the music recording industry when Sony introduced its PCM (Pulse Code Modulation) digital recording system as an encoding box / PCM adaptor that connected to a Betamax recorder. The Sony PCM-F1 adaptor was sold with a companion Betamax VCR SL-2000 as a portable digital audio recording system. Many recording engineers used this system in the 1980s and 1990s to make their first digital master recordings.
Initially, Sony was able to tout several Betamax-only features, such as BetaScan, a high speed picture search in either direction and BetaSkipScan, a technique that allowed the operator to see where he was on the tape by pressing the FF key (or REW, if in that mode) and the transport would switch into the BetaScan mode until the key was released. This feature is discussed more on Peep Search. Sony believed that the M-Load transports used by VHS machines made copying these trick modes impossible. BetaSkipScan (Peep Search) is now available on miniature M-load formats, but even Sony were unable to fully replicate this on VHS. BetaScan was originally called "Videola" until the company that made the Moviola threatened legal action.
Sony would also sell a BetaPak, a small deck designed to be used with a camera. Concerned with the need for several pieces, and cables to connect them, an integrated camera/recorder was designed, which Sony dubbed a "Camcorder". The result was Betamovie. Betamovie used the standard sized cassette, but with a modified transport. The tape was wrapped 300 degrees around a smaller, 44.671 mm diameter head drum, with a single dual-azimuth head to write the video tracks. For playback, the tape would be inserted into a Beta format deck. Due to the different geometry and writing techniques employed, playback within the camcorder was not feasible. SuperBeta and Industrial Betamovie camcorders would also be sold by Sony.
[edit] HiFi audio upgrade
Betamax introduced high fidelity audio to videotape, as Beta Hi-Fi. For NTSC, Betahifi worked by placing a pair of FM carriers between the chroma (C) and luminance (Y) carriers, a process known as audio frequency modulation. Each head had a specific pair of carriers, in total four individual channels were employed. Head A recorded its hifi carriers at 1.38(L) and 1.68(R) MHz, and the B head employed 1.53 and 1.83 MHz. The result was audio with an 80 dB dynamic range, with less than 0.005% wow and flutter.
Prior to the introduction of Beta Hi-Fi, Sony shifted the Y carrier up by 400 kHz to make room for the 4 FM carriers that would be needed for Beta Hi-Fi. All Beta machines incorporated this change, plus the ability to hunt for a lower frequency pre-AFM Y carrier. Sony incorporated an "anti-hunt" circuit, to stop the machine hunting for a Y carrier that wasn't there.
Some Sony NTSC models were marketed as "Hi-Fi Ready" (with an SL-HFR prefix to the model's number instead of the usual SL or SL-HF). These Betamax decks looked like a regular Betamax model, except for a special 28 pin connector on the rear. If the user desired a Beta Hi-Fi model but lacked the funds at the time, he could purchase an "SL-HFRxx" and at a later date purchase the separate Hi-Fi Processor. Sony offered two outboard Beta Hi-Fi processors, the HFP-100 and HFP-200. They were identical except that the HFP-200 was capable of multi-channel TV sound, with the word "stereocast" printed after the Beta Hi-Fi logo. This was possible because unlike a VHS Hi-Fi deck, an NTSC Betamax didn't need an extra pair of heads. The HFP-x00 would generate the needed carriers which would be recorded by the attached deck, and during playback the AFM carriers would be passed to the HFP-x00. They also had a small "fine tracking" control on the rear panel for difficult tapes.
For PAL however, the bandwidth between the chroma and luminance carriers was not sufficient enough to allow additional FM carriers, so depth multiplexing was employed, where the audio track would be recorded in the same way that the video track was. The lower frequency audio track was written first by a dedicated head, and the video track recorded on top by the video head. The head disk had an extra pair of audio only heads with a different azimuth, positioned slightly ahead of the regular video heads, for this purpose.
Sony was confident that VHS could not achieve the same audio performance feat as Beta Hi-Fi. However, to the chagrin of Sony, JVC did develop a VHS hi-fi system on the principle of depth multiplexing approximately a year after the first Beta Hi-Fi VCR, the SL-5200, was introduced by Sony. Despite initial praise as providing "CD sound quality", both Beta Hi-Fi and VHS HiFi suffered from "carrier buzz", where high frequency information bled into the audio carriers, creating momentary "buzzing" and other audio flaws. Both systems also used companding noise-reduction systems, which could create "pumping" artifacts under some conditions. Both formats also suffered from interchange problems, where tapes made on one machine did not always play back well on other machines. When this happened, users were forced to revert to the old linear soundtrack.
[edit] New standards – SuperBetamax and Extended Definition Betamax
In 1985 Sony would introduce a new feature, High Band or SuperBeta, by again shifting the Y carrier, this time by 800 kHz. This improved the bandwidth available to the Y sideband, and increased the horizontal resolution from 240 to 290 lines on a regular grade Betamax cassette. Since over-the-antenna and cable signals were only 300–330 lines resolution, SuperBeta could make a nearly-identical copy of live television. However, the chroma resolution still remained relatively poor, limited to just under 0.4 megahertz or approximately 30 lines resolution, whereas live broadcast chroma resolution was over 100 lines. The heads were also narrowed to 29 micrometers to reduce crosstalk, with a narrower head gap to play back the higher carrier frequency at 5.6 MHz. Later, some models would feature further improvement, in the form of Beta-Is, a high band version of the Beta-I recording mode. There were some incompatibilities between the older Beta decks and SuperBeta, but most could play back a high band tape without major problems. SuperBeta decks had a switch to disable the SuperBeta mode for compatibility purposes. (SuperBeta was only marginally supported, as many licensees had already discontinued their Betamax line.)
In 1988, Sony would again push the envelope with ED Beta or "Extended Definition" Betamax, capable of up to 500 lines of resolution, that equaled DVD quality (480 typical). In order to store the ~6.5 megahertz-wide luma signal, with the peak frequency at 9.3 MHz, Sony used a metal formulation tape from the Betacam (branded "ED-Metal"), and incorporated some improvements to the transport to reduce mechanically induced aberrations in the picture. Beta ED also featured a luminance carrier deviation of 2.5 MHz, as opposed to the 1.2 MHz used in SuperBeta, improving contrast with reduced luminance noise.
Sony introduced two ED decks and a camcorder in the late 1980s. The top end EDV-9300 deck was a very capable editing deck, rivalling much more expensive U-Matic setups for its accuracy and features, but did not have commercial success due to lack of timecode and other pro features. Sony did market Beta ED to "semi-professional" users, or "prosumers". One complaint about the EDC-55 ED CAM was that it needed a lot of light (at least 25 lux), due to the use of two CCDs instead of the typical single CCD imaging device. The Beta ED lineup only recorded in BII/BIII modes, with the ability to play back BI/BIs.
Despite the sharp decline in sales of Betamax recorders in the late 1980s and subsequent halt in production of new recorders by Sony in 2002, both Betamax and SuperBetamax are still being used by a small number of people, most of whom are collectors or hobbyists. New cassettes are still available for purchase at online shops and used recorders are often found at flea markets, thrift stores, or on internet auction sites. Early format BetaCam cassettes, which are physically based on the Betamax cassette, continue to be available for use in the professional media.
[edit] Comparison with other media
Here is a list of modern-day, digital-type measurements (and traditional, analog horizontal resolutions in TV lines per picture height) for various media. The list only includes popular formats, not rare formats, and all values are approximate (rounded to the nearest 10), since the actual quality can vary machine-to-machine or display-to-display. For PAL media, replace 480 with 576. For ease of comparison all values are for the NTSC system, and listed in ascending order from lowest to highest quality.
- 350×240 (250 lines): Video CD
- 330×480 (250 lines): Umatic, Betamax, VHS, Video8
- 400×480 (300 lines): Super Betamax, Betacam (professional), SVCD (Super Video CD)
- 440×480 (330 lines): analog broadcast
- 560×480 (420 lines): LaserDisc, Super VHS, Hi8
- 670×480 (500 lines): Enhanced Definition Betamax
- 720×480 (500 lines): DVD, miniDV, Digital8, Digital Betacam (professional)
- 720×480 (400 lines): Widescreen DVD (anamorphic)
- 1280×720 (700 lines): D-VHS, HD DVD, Blu-ray, HDV (miniDV)
- 1920×1080 (1000 lines): D-VHS, HD DVD, Blu-ray, HDCAM SR (professional)
[edit] Criticism
A multitude of technical drawbacks hurt Betamax in its competition with VHS.[citation needed] The main issue with the format in the early days of the North American market was recording time. The original prototypes shown to Matsushita used a linear tape speed of 40 mm/sec. The technology of the day needed that speed due to the 60 micrometer heads employed. Management had also told engineering to deliver a cassette about the size of a paperback book. Sony engineers and management decided that since one hour was acceptable to the U-Matic's buyers, it was acceptable for Betamax as well, and made a small cassette practical. They would find that home buyers wanted longer run times than professional U-matic users.
When, in 1976, RCA introduced a VHS recorder capable of storing 4 hours on a standard T-120 tape, Americans and Canadians flocked to the longer run time, as it was perfect for recording the evening primetime schedule or afternoon football games. Sony immediately realized that 1 hour was not sufficient and introduced Beta-2 and Beta-3 speeds, but the smaller form factor limited maximum record time to only 5 hours due to the smaller cassette; roughly half the time that a VHS cassette could hold.
[edit] See also
- Videotape format war
- Peep search – A picture search system pioneered with Betamax and available on most video formats since.
- Umatic - The predecessor to Betamax, using 3/4-inch tape instead of 1/2-inch.
- Compact Video Cassette - Competitor product developed by Funai and Technicolor using 1/4" tape format.
- Betacam - Umatic's replacement. A non-compatible, high-quality standard used by television studios and other professionals.
- Video8 - A small form factor tape based upon Betamax technology, using 8mm tape.
- Blu-ray Disc - Sony's latest video tech.
[edit] Notes and references
- ^ "This is a revolution!", Sony History, Sony.net
[edit] External links
- The Ultimate Betamax Info Guide – covering the Betamax format in the North American market]
- Mister Betamax – extensive Beta supply site
- Betamax PALsite – over 350 pages of Betamax information, running since 1997
- The 'Total Rewind' VCR museum – covering Betamax and other vintage formats
- The Betamax format in the UK, including technical information on servicing Sanyo Beta machines
- "Daily Giz Wiz" Podcast discussing the Betamax
- The Rise and Fall of Beta by Marc Wielage & Rod Woodcock
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