Appendix 6: Technical standards (2010)
Television and video production and distribution remains a fast-changing field with many competing (and sometimes confusing) technical systems in use. And there's a lot more change to come in the very near future.
Advances continue in collaborative computer-based video editing and high-volume data storage. The emergence of solid-state recording media (hard disc, optical disc, flashcard) signals a challenge to traditional reliance on recording to moving videotape formats, although to date tape formats remain dominant and offer significant advantages in storage capacity and cost.
On the TV transmission side, the switchover over to an all-digital service continues. Following the emergence of High Definition broadcasting in Japan and the USA, it has now arrived as a significant minority broadcast format in the UK, with offerings from FreeSat as well as the commercial satellite broadcaster.
In North America and Japan high definition video production has taken off, and it’s beginning to spread as a mainstream format for premium productions in the UK. The emerging ranges of high definition production equipment look enticing - HDTV quality at lower than DigiBeta prices. High resolution plasma and LCD screens are falling in price and steadily improving in quality this should continue to accelerate as manufacturing volumes rise. LED screens show great promise. Next-generation DVD players in the high definition BluRay format are now with us, though take-up to date is slow.
In this brave new HDTV world, though, there will still be "Format Wars". D5HD, DVCPRO HD, HDCAM, HDCAM SR, HDV, XDCAM HD all have merits; and Sony's and Panasonic's joint AVCHD might turn into something interesting.
Production using one of the many digital formats and technical routes available is the norm. There is a strong trend towards the completion of programmes entirely within computer-based non-linear editing systems. Linear edit suites continue to offer value to those who have invested in them, but are unlikely to be renewed as the tools of choice for (offline) editing an (online) finishing continue to change.
For Britain and Europe, Ofcom and the European Broadcast Union set standards for technical quality which terrestrial broadcasters are required to meet (except for news or special circumstances). (link to BBC guidelines on broadcast standards) Production to these standards allows for good quality DVD duplication, and for technical quality similar to a good off-air recording - the standards we have come to expect from home viewing.
Multichannel satellite broadcasting (in MPEG 2 format in the UK) has seen some dilution of the strict "broadcast technical quality" requirement.
Although current satellite channels do not carry full broadcast quality, their signal is much less subject to degradation in transmission and (it's hoped) decoding. So the viewer experiences a similar - sometimes even an improved - result, compared to viewing a full broadcast signal transmitted in the traditional analogue way. This may, over time, be reflected in changes in programme delivery requirements - and consequently in acceptable production routes. This may soften resistance to the (lower cost) near-broadcast quality technical systems capable of producing a Sky-quality result - mainly DVC Pro and DV CAM. For non-broadcast use, these formats already offer excellent results for DVD and VHS show copies.
There are reports that both ITV and the BBC have commissioned significant documentary series in DVCAM format.
The electronics industry remains keen to develop new production technologies, with HD and solid state recording near the top of the agenda.
Film and video production continue to converge, with many UK cinema productions finishing entirely through a digital intermediate (alt) production route, followed by digital to film transfer for distribution. Fully digital cinema production (including filming) continues to promise more than it delivers, with excellent cameras on the market from Thomson Arriflex, Silicon Imaging as well as high end lens support from Panavision, and more recently the Red project has moved from proposal to delivered product. As post production workflows become more practical and accessible and the cameras continue to improve in quality of output, ruggedness and reliability in the field, these technologies may challenge film origination for some kinds of cinema projects. Even at the lowest budget levels, production via HDTV formats is likely to replace standard-definition DV / DigiBeta for almost all cinema projects.
It's worth remembering, of course, that the various technical formats available each set the upper limits to what their users can achieve, but are susceptible to considerable variation; a dirty lens or low-end camera will produce poor results, even if those results are recorded perfectly on a high-end, uncompressed digital format. The skills of the director, performers, camera crew, editor and other technicians remain a determining factor in final quality; and of course the subject, script and programme approach are crucially important if a programme is to succeed.
High definition TV
High definition video equipment {Hi Def in the film world, or HDTV to those with more of a television background} has been around a long time, and there are a number of competing formats. All offer substantial advantages over conventional (standard definition) broadcast video. HDTV broadcasts are now established in some countries, including the USA and Japan, though the numbers of viewers with HiDef screens is, as yet, quite small.
HDTV's excellent picture quality offers great potential, provided the means are in place to show the finished programme in its full glory - on a suitable large screen, or using a high definition video projection system, or by transfer to film for projection.
Hi Def production is now practical, if still relatively expensive. To date it remains a relatively rare choice in Europe. As trends in Japan and the USA towards high-definition production continue to strengthen, this may change over here in the near future.
The appeal for low-budget film makers planning an eventual transfer to film for distribution will be considerable. It would be no surprise were a number of businesses and organisations to want to use the new formats to make a splash at events, exhibitions or elsewhere, and traditional broadcasters will no doubt be examining both the cost and the quality developments closely.
There are a number of different technical routes under the HDTV umbrella. The two with early market dominance are:
Sony's HDCam (usually "1080i" - that is at a nominal 1920x 1080 resolution with interlaced frames, and 24 or 25 fps - but a number of variants are possible) ,
and Panasonic's DVCProHD (usually "720p" - that is, a nominal 1290x 720 resolution with progressive scan frames, and again typically 24 or 25 fps).
Both these formats downsample the nominal picture dimensions to manage data rates, and both use quite a lot of compression - nevertheless, the results can be excellent.
Sony’s HDCAM SR goes a step further - full colour sampling (4:4:4 instead of a nominal 3:1:1; full screen resolution; apparently no compression - but as a result, more data to handle.)
Sony's (promotional) guide to choosing an HD camera may be of interest.
Sony’s XDCAM HD format offers decent quality at reduced data rates (more economical editing, if at the cost of some quality loss).
HDV offers a hint or echo of the DV revolution that blew away much fusty, traditional production technique and approach in the standard definition era. The best of the HDV models available offer decent quality at lower cost (than HDCAM). The camera equipment is lightweight and relatively easy to use, capable of accepting high-end lenses (some camera models only!), and of recording either to tape in camera (with heavy compression in HDV format) or of feeding a location hard disc recorder to capture direct to a less compressed, better for editing format such as one of Cineform’s.
Broadcast quality- digital:
A number of digital formats are at present available in the UK, including;
Digital Betacam - 1/2" component from Sony, using 2:1 data compression. The dominant format. Digi Beta machines can play back earlier Betacam formats, so that archive footage can easily be incorporated into current production.
DVCPro50 - Panasonic's full broadcast system, recording onto DV-width tapes. Excellent quality and value.
MPeg2 IMG - Sony broadcast mpeg 2 variant, recordable direct to optical disc on is XDCAM camcorders Has achieved considerable sales success in mainland Europe, if less so in the UK to date.
D5 - 1/2" component from Panasonic, does not use data compression. Originally Channel 4's required delivery format - now they accept D5 or Digi Beta. The strengths of D5 in technical quality are offset by the lack of camera systems recording on this format, though it is currently favoured as a mastering format for some high-end HDTV and film-destined productions.
Digital S, also known as D9; 1/2" digital component from JVC, using low (3.3:1) compression and generating broadcast quality. High quality and low prices have yet to bring a breakthrough in the market, perhaps partly because of Sony’s clout, and the ability of Digi Beta and Beta SX machines to play back the vast amount of Betacam SP material which producers hold
Betacam SX - alternative digital format from Sony, offering lower quality and cost than Digital Betacam, and initially aimed at news organisations. Uses MPEG 2 compression. Offers choice of traditional or widescreen aspect ratios. To date few Beta SX edit suites have emerged - the source material has typically been mastered onto digital Betacam or D5.
Record to Disc and solid-state. Camcorders that bypass tape altogether and record directly onto hard disc or to f;lash drive cards are available, both at a pro level (see MPeg2 IMG / XD) and for the domestic market. Some think that this is the likely direction in the medium term. Others think this may take a long time to emerge as a mainstream shooting format.
Sometimes used for broadcast::
DVCPro Close to broadcast quality at low cost from a 6mm tape using 6:1 data compression.( Full broadcast quality version DVC Pro 50 is also available.)
DVCAM; a competitor to DVCPro. Sony's record of success in broadcast video makes any format they back a contender, though their Betamax domestic system and DCC audio system both failed commercially. Neither DV Cam nor DVC Pro reach full broadcast standard, though both are much used for broadcast work.
DV (Digital Video) High-quality domestic standard, and the platform from which DVC Pro and DV Cam have been developed. DV camcorders are sometimes used for broadcast production when considerations of speed and ease of access take precedence over technical quality.
Other well-known digital formats include:
D1 This was the original broadcast digital video system, and is still widely used for compositing graphics. Does not use data compression. D1 features excellent technical quality, but high prices, and has lost some ground to Digital Betacam
Broadcast quality - film formats:
Film still has a significant share of the production market, both for TV and for promotional and training productions where projection to a large audience is necessary. Film gives the best results for large-screen projection, and offers very high quality as a source for video.
35mm: The standard format for cinema films and much TV advertising. Sometimes used for major public relations events, and presentations such as new car launches.
16mm / super 16 mm: Used for some TV drama and big-budget documentary. In the business world, a high-quality option when projection to a large audience is desired. Film is also often as the original recording medium with the results then transferred to computer disc or videotape for editing.
format archive
|
