|Media type||Magnetic cassette tape|
|Encoding||NTSC, PAL, High-definition video|
|Read mechanism||Helical scan|
|Write mechanism||Helical scan|
|Standard||Interlaced video, Progressive video|
|Released||August 7, 1982|
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.
All Betacam variants from (plain) analog recording Betacam to Betacam SP and digital recording Digital Betacam (and additionally, HDCAM and HDCAM SR), use the same shape videocassettes, meaning vaults and other storage facilities do not have to be changed when upgrading to a new format. The cassettes are available in two sizes: S (for Short) and L (for Long). The Betacam camcorder can only load S magnetic tapes, while television studio sized video tape recorders (VTR) designed for video editing can play both S and L tapes.
The cassette shell and case for each Betacam cassette is colored differently depending on the format, allowing for easy visual identification. There is also a mechanical key that allows a video tape recorder to identify which format has been inserted.
The format supplanted the three-quarter-inch U-Matic format, which Sony had introduced in 1971. In addition to improvements in video quality, the Betacam configuration of an integrated professional video camera/recorder led to its rapid adoption by electronic news gathering (ENG) organizations.
DigiBeta, the common name for Digital Betacam, went on to become the single most successful professional broadcast digital recording video tape format in history, but now although Betacam remains popular in the field and for archiving, new tapeless digital products have led to a phasing out of Betacam products in television studio environments since as of 2006.[ citation needed ]
The original Betacam format was launched on August 7, 1982. It is an analog component video format, storing the luminance, "Y", in one track and the chrominance, on another as alternating segments of the R-Y and B-Y components performing Compressed Time Division Multiplex, or CTDM.This splitting of channels allows true broadcast quality recording with 300 lines of horizontal luminance resolution and 120 lines chrominance resolution versus 0.4 MHz chroma bandwidth for Betamax/VHS (~30 lines resolution left-to-right) on a relatively inexpensive cassette based format.
The original Betacam format records on cassettes loaded with ferric oxide–formulated tape, which are theoretically the same as used by its consumer market-oriented predecessor Betamax, introduced seven years earlier by Sony in 1975. A blank Betamax-branded tape will work on a Betacam deck, and a Betacam-branded tape can be used to record in a Betamax deck. However, in later years Sony discouraged this practice, suggesting that the internal tape transport of a domestic Betamax cassette was not well suited to the faster tape transport of Betacam. In particular, the guide rollers tend to be noisy.
Although there is a superficial similarity between Betamax and Betacam in that they use the same tape cassette, they are really quite different formats. Betamax records relatively low resolution video using a heterodyne color recording system and only two recording heads, while Betacam uses four heads to record in component format, at a much higher linear tape speed of 10.15 cm/s (3.99606 in./s) compared with Betamax's 1.87 cm/s (0.7362205 in./s), resulting in much higher video and audio quality. A typical L-750 length Betamax cassette that yielded about 3 hours of recording time on a Betamax VCR at its B-II Speed (NTSC), or on PAL, only provided 30 minutes' record time on a Betacam VCR or camcorder. Another common point between Betamax and Betacam is the placement of the stereo linear audio tracks.[ citation needed ] Also, some Betacam and Betamax portables share the same batteries.
(Matsushita's rival "M" and "MII" formats took a similar approach in combining the cassette from a non-professional system- in this case, VHS- with a much higher-quality recording format. However, neither enjoyed Betacam's level of success).
Betacam was initially introduced as a camera line along with a video cassette player. The first cameras were the BVP-3, which utilized three saticon tubes, and the BVP1, which used a single tri-stripe Trinicon tube. Both these cameras could be operated standalone, or with their docking companion VTR, the BVV-1 (quickly superseded by the BVV-1A), to form the BVW-1 (BVW-1A) integrated camcorder. Those decks were record-only. The only transport controls on the deck were Eject and Rewind. The docked camera's VTR button started and paused the tape recorder. Later the Betacam SP docking decks had full transport controls (except a Record button) but tapes could not be played back except in the camera's viewfinder in black-and-white only. Sony then came out with the Play Adapter, a separate portable unit that connected via a multi-pin cable and had a composite video out jack for color playback. At first color playback required the studio source deck, the BVW-10, which could not record, only play back. It was primarily designed as a feeder deck for A/B roll edit systems, usually for editing to a one-inch Type C or three-quarter-inch U-matic cassette edit master tape. There was also the BVW-20 field playback deck, which was a portable unit with DC power and a handle, that was used to verify color playback of tapes in the field. Unlike the BVW-10, it did not have a built in Time Base Corrector, or TBC.
With the popular success of the Betacam system as a news acquisition format, the line was soon extended to include the BVW-15 studio player, and the BVW-40 Studio Edit Recorder. The BVW-15 added Dynamic Tracking, which enabled clear still frame and jog playback, something the BVW-10 could not deliver. The BVW-40 enabled for the first time editing to a Betacam master, and if set up and wired correctly, true component video editing. It was also possible to do machine to machine editing between a BVW-10/15 and BVW-40 without an edit controller—a single serial cable between the units was all that was required to control the player from the recorder in performing simple assemble and insert editing. Additionally there were two field models introduced, the field recorder BVW-25, and the BVW-21 play only portable field deck.
At its introduction, many insisted that Betacam remained inferior to the bulkier one-inch Type C and B recording, the standard broadcast production format of the late 1970s to mid-1980s. Additionally, the maximum record time for both the cameras and studio recorders was only half an hour, a severe limitation in television production. There was also the limitation that high quality recording was only possible if the original component signals were available, as they were in a Betacam camcorder. If the recording started as composite video, re-converting them to components for recording and then eventually back to composite for broadcast caused a drop in quality compared to recording component video directly.
In 1986, Betacam SP (commonly referred to as Beta SP) was developed, which increased horizontal resolution to 340 lines. While the quality improvement of the format itself was minor, the improvement to the VTRs was enormous, in quality, features, and particularly, the new larger cassette with 90 minutes of recording time. Betacam SP (for "Superior Performance") became the industry standard for most TV stations and high-end production houses until the late 1990s. Despite the format's age Betacam SP remained a common standard for standard definition video post-production into the 2010s. The recording time is the same as for Betacam, 30 and 90 minutes for S and L, respectively. Tape speed is slightly slower in machines working in the 625/50 format, increasing tape duration by one minute for every five minutes of run time. So, a 90-minute tape will record 108 minutes of video in PAL.
Betacam SP is able to achieve its namesake "Superior Performance" over Betacam in the fact that it uses metal-formulated tape as opposed to Betacam's ferric oxide tape. Sony designed Betacam SP to be partially forward compatible with standard Betacam, with the capability that Betacam SP tapes recorded on Betacam SP decks can be played in oxide-era Betacam VTRs (such as the BVW-15 and BVW-40 mentioned earlier), but for playback only. Betacam SP-branded tapes cannot be used for recording in consumer Betamax VCRs like oxide Betacam tapes, due to Betacam SP's metal-formulation tape causing the video heads in a Betamax deck to wear prematurely, which are made of a softer material than the heads in a standard Betacam deck. However, Betacam SP tapes can be used without a problem in ED Beta VCRs, since the ED Beta format uses metal-formulated tape as well.
The new Betacam SP studio decks were the players: The BVW-60 and BVW-65 (the BVW-65 features Dynamic Tracking); and the Edit Recorders: the BVW-70, and the Dynamic Tracking model, the BVW-75. The BVV-5 was the Betacam SP dockable camera back, which could play back in color if its companion playback adapter was used. A new SP field recorder, the BVW-35, possessed the added benefit of a standard RS422 serial control port that enabled it to be used as an edit feeder deck. Though the four new studio decks could utilize the full 90-minute Betacam SP cassettes, the BVW-35 remained limited to the original Betacam small 30-minute cassette shells. Answering a need for a basic office player, Sony also introduced the BVW-22, a much less expensive desktop model that could be used for viewing and logging 90-minute cassettes of both BetacamSP and oxide types, but could not be configured into an edit system and offered only Composite Video output.
Sony followed up the SP Field Recorder with the BVW-50, that could record and play the large-size 90 minute cassettes. After this, the deck line was relatively stagnant and incredibly popular for a decade, aside from some specialty models that could record digital audio. Some Betacam SP VCRs were sold by Broadcast Television Systems Inc. (BTS).
Until the introduction of the BVW-200 camera though, the camera and recorder configuration was a docking system. The BVW-200 was an integrated camera recorder system. It sacrificed the flexibility of a docking camera in order to lose a substantial amount of weight. Eventually, non-docking camcorders became the most popular design by the mid-1990s.
The final Betacam SP camcorder was the BVW-600, which paired a digital professional video camera front section, very similar to the one on the DigiBeta DVW-700, with an integrated Betacam SP recorder. Like every other Betacam camera system, and unlike the DigiBeta DVW-700, the camera could not play back in color without the use of an outboard adapter.
In 1991, the less-expensive, "Professional", PV line of Betacam SP decks was introduced. The PV line consisted of only four models: the full-sized PVW-2600 (VTP), PVW-2650 (VTP with Dynamic tracking allowing up to fwd x3, whereas the BVW line only offered x2 DT playback) and PVW-2800 (VTR) editing decks, and the PVV-3 camera-dockable VTR. These high quality machines were similar to the original BV series machines, but lacked the third and fourth audio channels. In 1993, the far less expensive UVW series debuted. These machines were considerably simpler, somewhat lower quality, and were designed primarily to be used as companions to computer systems, for industrial video, and other low-cost, yet high-quality, uses. The UVW decks possessed very limited front panel controls, no jog and shuttle (except by use of a DSRM-10 cable remote control); and with Time Base Corrector (TBC) control available only with an optional remote TBC controller. These were represented by the UVW-1800, a very popular editing VTR (and companion UVW-1600 edit VTP), and the non-editing UVW-1400 VTR, and UVW-1200 VTP. The UVW-100 (and later 100B) one-piece camcorder rounded out the UVW series.
Betacam and Betacam SP tape cassette shells varied in color depending on the manufacturer. Many companies sold Betacam tapes, sometimes of their own manufacture, sometimes re-branded. Fuji, Maxell, Ampex and 3M were just some of the major brands to do so.
Ampex, Thomson SA and Philips each sold rebranded OEM versions of some of the Sony VTRs and camcorders at various times in the 1980s and 1990s. Other than nameplates, these models were identical to the Sony models. Internal components still bore the Sony name.
Digital Betacam (commonly referred to as DigiBeta, D-Beta, DBC or simply Digi) was launched in 1993. It supersedes both Betacam and Betacam SP, while costing significantly less than the first, 100% uncompressed D1 format. S tapes are available with up to 40 minutes running time, and L tapes with up to 124 minutes.
The Digital Betacam format records 2.34:1 DCT-compressed digital component video signal Mbit/s plus four channels of uncompressed 48 kHz / 20 bit PCM-encoded digital audio. A fifth analog audio track is available for cueing, and a linear timecode track is also used on the tape. It was a popular digital video cassette format for broadcast television use.at 10-bit YUV 4:2:2 sampling in NTSC (720×486) or PAL (720×576) resolutions at a bitrate of 90
Another key element which aided adoption was Sony's implementation of the SDI coaxial digital connection on Digital Betacam decks. Facilities could begin using digital signals on their existing coaxial wiring without having to commit to an expensive re-installation.
Betacam SX is a digital version of Betacam SP introduced in 1996, positioned as a cheaper alternative to Digital Betacam. It stores video using MPEG-2 4:2:2 Profile@ML compression, along with four channels of 48 kHz 16 bit PCM audio. All Betacam SX equipment is compatible with Betacam SP tapes. S tapes have a recording time up to 62 minutes, and L tapes up to 194 minutes.
The Betacam SX system was very successful with newsgathering operations, which had a legacy of Betacam and Betacam SP tapes. Some Betacam SX decks, such as the DNW-A75 or DNW-A50, can natively play and work from the analog tapes interchangeably, because they contain both analog and digital playback heads.
Betacam SX uses MPEG-2 4:2:2P@ML compression, in comparison with other similar systems that use 4:1:1 or 4:2:0 coding. It gives better chroma resolution and allows certain postproduction processes such as Chroma-key.
This format compresses the video signal from approximately 180 Mbit/s to only 18 Mbit/s. This means a compression ratio of around 10:1, which is achieved by the use of mild temporal compression, where alternate frames are stored as MPEG I-frames and B-frames, giving rise to an IBIB sequence on tape.
Together with Betacam SX, Sony introduced a generation of hybrid recorder, allowing use of both tape and disk recording on the same deck, and high speed dubbing from one to another. This was intended to save wear on the video heads for television studio applications, as well to speed up online editing.
Betacam SX also features a good shot mark (a method for qualitative decisions made in the camcorder to be utilized during the editing process) feature that allows marking of each scene for fast scanning of the tape, looking at recorded marks on each single cassette, and showing the markers to the operator.
The cameras themselves are generally considered by most sound recordists to be quite noisy in operation, possibly because the amount of computer processing power, and subsequent generated heat leads to cooling fans being used to keep the camera at a reasonable temperature.
Betacam SX tape shells are bright yellow, but SX recordings may also be found recorded on analogue Betacam SP cassettes. Of course if such a Betacam SP tape with SX recording is inserted into a Betacam SP player, no picture or sound will appear.
Although Betacam SX machines have gone out of production, the format is still used by many newsgathering operations, including CNN, Canada's CTV, Atlanta's WSB-TV, San Diego's KFMB-TV and NBC's operations in the San Francisco Bay Area at KNTV and KSTS. Many news archives still contain SX tapes. In August 2011, Betacam SX tapes were found in Muammar Gaddafi's underground studio in Tripoli. CNN reporter Sara Sidner commented on-air that CNN still used the same type of tapes.
MPEG IMX is a 2001 development of the Digital Betacam format. Digital video compression uses H.262/MPEG-2 Part 2 encoding at a higher bitrate than Betacam SX: 30 Mbit/s (6:1 compression), 40 Mbit/s (4:1 compression) or 50 Mbit/s (3.3:1 compression). Unlike most other MPEG-2 implementations, IMX uses intraframe compression. Additionally, IMX ensures that each frame has the same exact size in bytes to simplify recording onto video tape. Video recorded in the IMX format is compliant with CCIR 601 specification, with eight channels of audio and timecode track. It lacks an analog audio (cue) track as the Digital Betacam, but will read it as channel 7 if used for playback. This format has been standardized in SMPTE 365M and SMPTE 356M as "MPEG D10 Streaming".
With its IMX VTRs, Sony introduced some new technologies including SDTI and e-VTR. SDTI allows for audio, video, timecode, and remote control functions to be transported by a single coaxial cable, while e-VTR technology extends this by allowing the same data to be transported over IP by way of an ethernet interface on the VTR itself.
All IMX VTRs can natively playback Betacam SX tapes, and some, such as the MSW-M2000P/1 are capable of playing back Digital Betacam cassettes as well as analog Betacam and Betacam SP cassettes, but they can only record to their native IMX cassettes. S tapes are available with up to 60 minutes capacity, and L tapes hold up to 184 minutes. These values are for 525/60 decks, but will extend in 625/50. A 184-minute tape will record for, as the label itself specifies, 220 minutes.
IMX machines feature the same good shot mark function of the Betacam SX.
MPEG IMX cassettes are a muted green.
The XDCAM format, unveiled in 2003, allows recording of MPEG IMX video in MXF container onto Professional Disc.
HDCAM, introduced in 1997, was the first HD format available in Betacam form-factor, using an 8-bit DCT compressed 3:1:1 recording, in 1080i-compatible downsampled resolution of 1440×1080, and adding 24p and 23.976 PsF modes to later models. The HDCAM codec uses non-square pixels and as such the recorded 1440×1080 content is upsampled to 1920×1080 on playback. The recorded video bitrate is 144 Mbit/s. There are four channels of AES/EBU 20-bit/48 kHz digital audio.
It was used for some of Sony's cinema-targeted CineAlta range of products (other CineAlta devices use flash storage).
HDCAM SR, introduced in 2003, uses a higher particle density tape and is capable of recording in 10 bits 4:2:2 or 4:4:4 RGB with a bitrate of 440 Mbit/s. The "SR" stands for "Superior Resolution". The increased bitrate (over HDCAM) allows HDCAM SR to capture much more of the full bandwidth of the HD-SDI signal (1920×1080). Some HDCAM SR VTRs can also use a 2× mode with an even higher bitrate of 880 Mbit/s, allowing for a 4:4:4 RGB stream at a lower compression. HDCAM SR uses the new MPEG-4 Part 2 Studio Profile for compression, and expands the number of audio channels up to 12 at 48 kHz/24 bit.
HDCAM SR was used commonly for HDTV television production.
Some HDCAM VTRs play back older Betacam variants, for example, the Sony SRW-5500 HDCAM SR recorder, plays back and records HDCAM and HDCAM SR tapes and with optional hardware also plays and upconverts Digital Betacam tapes to HD format. Tape lengths are the same as for Digital Betacam, up to 40 minutes for S and 124 minutes for L tapes. In 24p mode the runtime increases to 50 and 155 minutes, respectively.
Sony branded HDCAM cassettes are black with an orange lid, and HDCAM SR cassettes black with a cyan lid.
440 Mbit/s mode is known as SQ, and 880 Mbit/s mode is known as HQ, and this mode has recently become available in studio models (e.g. SRW-5800) as well as portable models previously available.
Digital video is an electronic representation of moving visual images (video) in the form of encoded digital data. This is in contrast to analog video, which represents moving visual images in the form of analog signals. Digital video comprises a series of digital images displayed in rapid succession.
Magnetic tape is a medium for magnetic recording, made of a thin, magnetizable coating on a long, narrow strip of plastic film. It was developed in Germany in 1928, based on magnetic wire recording. Devices that record and playback audio and video using magnetic tape are tape recorders and video tape recorders respectively. A device that stores computer data on magnetic tape is known as a tape drive.
VHS is a standard for consumer-level analog video recording on tape cassettes.
DV refers to a family of codecs and tape formats used for storing digital video, launched in 1995 by a consortium of video camera manufacturers led by Sony and Panasonic. In the late 1990s and early 2000s, DV was strongly associated with the transition from analog to digital desktop video production, and also with several enduring "prosumer" camera designs such as the Sony VX-1000. DV is sometimes referred to as MiniDV, which was the most popular tape format using a DV codec during this time.
Videotape is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog signal or digital signal. Videotape is used in both video tape recorders (VTRs) or, more commonly, videocassette recorders (VCRs) and camcorders. Videotapes are also 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. Shortly, later in the same year of 1987, first S-VHS VCR models from other competitors included Hitachi VT-2700A, Mitsubishi HS-423UR, Panasonic PV-S4764, and Toshiba SV-950.
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.
D-1 or 4:2:2 Component Digital is an SMPTE digital recording video standard, introduced in 1986 through efforts by SMPTE engineering committees. It started as a Sony and Bosch - BTS product and was the first major professional digital video format. SMPTE standardized the format within ITU-R 601, also known as Rec. 601, which was derived from SMPTE 125M and EBU 3246-E standards.
A camcorder is an electronic device originally combining a video camera and a videocassette recorder.
A video tape recorder (VTR) is a tape recorder designed to record and play back video and audio material from magnetic tape. The early VTRs were open-reel devices that record on individual reels of 2-inch-wide 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 modern 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 for the NTSC and PAL/SECAM television systems. These are the original Video8 format and its improved successor Hi8, as well as a more recent digital recording format known as Digital8.
MicroMV is a proprietary videotape format introduced in October 2001 by Sony. It is the smallest videotape format — 70% smaller than MiniDV or about the size of two US quarter coins; it is also smaller than a Digital8 or DV cassette and slightly smaller than an audio microcassette. It was the first helical scan tape system using MR read head introduced to the market. Each cassette can hold up to 60 minutes of video.
A recording head is the physical interface between a recording apparatus and a moving recording medium. Recording heads are generally classified according to the physical principle that allows them to impress their data upon their medium. A recording head is often mechanically paired with a playback head, which, though proximal to, is often discrete from the record head.
HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon, and Sharp. The four companies formed the HDV Consortium in September 2003.
U-matic 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.
XDCAM is a series of products for digital recording using random access solid-state memory media, introduced by Sony in 2003. Four different product lines – the XDCAM SD, XDCAM HD, XDCAM EX and XDCAM HD422 – differ in types of encoder used, frame size, container type and in recording media.
HDCAM is a high-definition video digital recording videocassette version of Digital Betacam introduced in 1997 that uses an 8-bit discrete cosine transform (DCT) compressed 3:1:1 recording, in 1080i-compatible down-sampled resolution of 1440×1080, and adding 24p and 23.976 progressive segmented frame (PsF) modes to later models. The HDCAM codec uses rectangular pixels and as such the recorded 1440×1080 content is upsampled to 1920×1080 on playback. The recorded video bit rate is 144 Mbit/s. Audio is also similar, with four channels of AES3 20-bit, 48 kHz digital audio. Like Betacam, HDCAM tapes were produced in small and large cassette sizes; the small cassette uses the same form factor as the original Betamax. The main competitor to HDCAM was the DVCPRO HD format offered by Panasonic, which uses a similar compression scheme and bit rates ranging from 40 Mbit/s to 100 Mbit/s depending on frame rate.
D-9 or Digital-S as it was originally known, is a professional digital video videocassette format created by JVC in 1995.
A videocassette recorder (VCR) or video recorder is an electromechanical device that records analog audio and analog video from broadcast television or other source on a removable, magnetic tape videocassette, and can play back the recording. Use of a VCR to record a television program to play back at a more convenient time is commonly referred to as timeshifting. VCRs can also play back prerecorded tapes. In the 1980s and 1990s, prerecorded videotapes were widely available for purchase and rental, and blank tapes were sold to make recordings.