History
of VideoTape - VHS
Videotape is a means of recording television pictures
and accompanying sound onto magnetic tape as opposed
to movie film. In virtually
all cases, a helical scan video head rotates
against the moving tape, because video signals have a very
high bandwith, and static heads would require extremely high
tape speeds. Video tape is used both invideo tape recorders
(VTRs or, more common, video cassette recorders (VCRs))
and video cameras. Tape is a linear method of storing
information, and since nearly all video recordings made nowadays
are digital, it is expected to gradually lose importance
as non-linear/random access methods of storing digital video
data are becoming more common.
History
Professional and broadcast use
Open reel
The first practical professional videotape machines were
the Quad machines introduced by Ampex in the United States
in 1956. Quad employed a helical scan system on a two-inch
(5 cm) tape. The BBC experimented with a high-speed linear
videotape system called VERA but this was ultimately unsuccessful,
and all subsequent videotape systems have used helical scan.
Although Quad became the industry standard for 20 years,
it had drawbacks such as an inability to freeze pictures,
and in early machines, a tape could only reliably be played
back using the same set of hand-made tape heads, which wore
out very quickly. Despite these problems, Quad could produce
excellent images. Unfortunately, very few early videotapes
still exist. The high cost of early videotapes meant that
most broadcasters erased and reused them, and regarded videotape
as simply a better and more cost-effective means of time-delaying
broadcasts than the previous kinescope technology, which
recorded television pictures onto photographic film. However,
some early broadcast videotapes have survived, including
The Edsel Show, broadcast live in 1957, and 1958's An Evening
With Fred Astaire, the oldest color broadcast videotape known
to exist.
The next format to gain widespread usage was the 1" C-format
videotape. It introduced features such as shuttling and still
framing.
The first video cassettes
Then, in 1969, Sony introduced the first widespread video
cassette (prior formats had used open reels), the 3/4" composite
U-matic system, which it later refined to Broadcast Video
U-matic or BVU. Sony continued its hold on the professional
market with its ever-expanding 1/2" component video
Betacam family (introduced in 1982), which, in its digital
variants, is still among the market leaders. Panasonic had
some limited success with ist MII system, but never could
compare to Betacam in terms of market share.
Going digital
The next step was the digital revolution. Among the first
digital video formats Sony's D1, which featured uncompressed
digital component recording. Because D1 was extremely expensive,
the composite D2 and D3 (by Sony and Panasonic, respectively)
were introduced soon after. Ampex introduced the first compressed
component recording with its Ampex DCT series in 1992. Panasonic
trumped D1 with its D5 format, which was uncompressed as
well, but much more affordable. JVC developed the S-VHS-based
D9 format, which compresses video data in a way similar to
DVCPRO.
For camcorders, Sony adapted the Betacam system with is
Digital Betacam format, later following it up with the more
low-cost Betacam SX and MPEG IMX formats, and the semiprofessional
DV-based DVCAM system. Panasonic used its DV variant DVCPRO
for all professional cameras, with the higher end format
DVCPRO50 being a direct descendant.
High definition
The introduction of HDTV production neccesitated a medium
for storing high resolution video information. In 1997, Sony
bumped its Betacam series up to HD with the HDCAM standard
and its higher-end cousin HDCAM SR. Panasonic's competing
format for cameras was based on DVCPRO and called DVCPRO
HD. For VTR and archive use, Panasonic expanded the D5 specification
to store compressed HD streams and called it D5 HD.
Consumer use
Home VCRs
The first domestic videocassette recorders were launched
in the early 1970s, but it was not until the Japanese systems,
Sony's Beta (1975) and JVC's VHS, were launched, that videotape
moved into the mass market, resulting in what came to be
known as the "format wars". VHS finally won, mainly
due to its longer recording time compared to Beta. VHS is
still the leading consumer VCR format, since its follow-ups
S-VHS and D-VHS never caught up on popularity. It has, however,
lost the battle against the nonlinear and disc based DVD,
and will probably become obsolete in the next few years.
Camcorders
In camcorders, however, the field was more diverse, with
the first formats to gain popularity being the 8mm video
format (later replaced by Hi8 and its DV hybrid relative
Digital8) and VHS-C (compact) tape. Now, MiniDV is the leading
media for camcorder use. However, consumer MiniDV VCRs did
not really catch on. Sony tried to introduce a new camcorder
tape with MicroMV, but consumer interest has been low. For
high definition, the most promising system seems to be the
new MiniDV-based HDV.
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