Broadcast quality - analogue:
Traditional analogue production systems are currently being replaced by digital systems, though organisations with large investments in analogue equipment will no doubt keep it running as long as possible. Of the main analogue systems, only Betacam SP retains a significant place in the production sector..
Betacam SP (component): Once dominant for broadcast both for production and as an edit format, and still widely used for promotional video programmes. Broadcast quality in its original "BVW" version, though to extend its dominance Sony introduced two lower cost variants, known as PVW and UVW.
Betacam was one of two early tape formats built on the "component" idea - recording separate "raw" streams of data to represent different components of the video signal (red, green and blue, or in Betacam's case, luminance, red minus luminance, blue minus luminance) rather than a single combined ("composite") stream, like PAL or NTSC. Component proved to give excellent data handling and picture quality, and is now used, in one or other variant, in most digital video systems.
Sub-broadcast:
A number of formats are in widespread use which do not meet broadcast standards, but are cheaper. Recent years have seen steady improvements in lightweight domestic camcorders recording onto a variety of tape formats. These can be coupled to PCs (or Macs) to deliver a budget version of desktop video, though as yet this approach has attracted only a small part of the professional market. The most prominent domestic formats are:
DV (Digital Video) Domestic digital videotape, using small tapes and low compression ratios (6:1): offers spectacular improvement on VHS in quality. The quality is close to broadcast, and should not degrade in editing so long as repeated decompressing and recompressing of the video data is avoided. As low-cost DV production equipment (camcorders and edit machines) become more widely used, they may turn the whole video production world upside down.
VHS and S-VHS: VHS is the dominant format for domestic video, and offers reasonable playback quality from original recordings. As quality falls each time the original is copied, to edit or to make show copies, VHS is not much used for production except for home movies and weddings.
S-VHS offers an improvement on VHS, particularly in picture resolution, but is weak on colour handling in editing and has not been taken up professionally except where cost pressures are extreme; after editing, picture quality falls below the quality produced on high-band U-matic.
Digital 8: Sony hybrid format that records DV signals onto
Hi- 8 tape. Little take-up for professional use.
Other contenders:
D-VHS Digital variant of VHS offering very high picture and sound quality, widescreen compatibility, and the ability to play back standard VHS tapes. Little take up to date.
DVD RECORDABLE A format that could be immensely significant; recordable DVD seems set to replace home VHS tape units, much as CD took over the mass market from tape and vinyl for audio. DVD recordable is also a strong computer format; this is an area of convergence in video and computing technology. Domestic camcorders which record direct to DVD are now on the market.
Historic note: formats we have loved.
D2 Digital composite - the colour signals are combined into a single signal, using the PAL colour system in the UK; this gives less good results than component when used for editing. This format looks likely to die out.
D3 1/2" digital composite on portable cassettes; a strong early contender for location recording, and accepted and used by the BBC for the Barcelona Olympics. Looks likely to die out.
1"C format (composite): Ageing, high-quality tape standard, once the dominant workhorse for studio production and as the master or source tape for bulk duplication of VHS copies. Broadcast quality. Now more or less obsolete.
M11 (component): Similar to Betacam SP, and of equivalent quality, but never widely adopted and now little used. Broadcast quality.
Video 8mm, Hi-8: These formats are interesting because they use extremely small tapes, and tiny cassette players (not much bigger than a standard audio-cassette walkman) are available. They offer slightly higher quality than their VHS counterparts, but have not achieved wide acceptance except for camcorder use.
Video 8mm is mainly used as a domestic camcorder format, and partly because it allows for small, light camera kit with long recording times it achieved some success, at one time taking well over half of the camcorder market. There are many video 8 camcorders still in use.
Hi-8 is a later variant of video 8mm offering improved quality in a very compact form.
The U-matic family of formats, a 3/4" tape, cassette-based family first launched by Sony as a home recording and display format in the late 70s. These offer good playback quality, and were used for news gathering in the late 70s and early 80s. They are now mainly used for production where cost-saving is paramount; particularly for training programmes for internal audiences. Likely to disappear as cheap digital formats emerge
Some of these U-matic formats are frequently and wrongly described by their owners or proponents as "broadcast standard", although they fall way below EBU/ITC standards and are not normally allowable for UK broadcast. The main U-Matic formats in current use are:
U-matic SP and High Band U-matic(also known as BVU): still used in a few organisations for producing internal training videos, this was widely used for promotional films until the mid-80s and the spread of the Betacam formats.
Low Band U-matic: though this was mainly used as playback format, it as sometimes used for production. Likely to give way entirely to DV production and DVD distribution anytime soon ...
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