Behind the scenes at Sony's 3D research centre
It's been quite a week for 3D TV: Samsung had a ritzy launch in New York, Panasonic has announced a tie-up with Best Buy in the US and LG has brought forward its plans for the launch of 3D TV in the UK.
With so much PR hype hitting the airwaves, an invitation to Sony's UK R&D centre in Basingstoke – where some of the engineers responsible for making 3D film and TV work are based – was too good an opportunity to miss.
Basingstoke may not be the most glamorous town in the world, but it is the nerve centre of Sony's professional broadcasting business. What these guys don't know about TV and film making probably isn't worth knowing.
Right now, the focus is all on 3D. Despite what you may have read elsewhere, it wasn't only Panasonic cameras that were used in the making of Avatar. James Cameron may have a promotion deal with Panasonic, but Sony cameras and technology played their part too. And Sony's 3D lab in California has worked on Tim Burton's 3D film of Alice in Wonderland, while Sony Pictures will release Clouding With a Chance of Meatballs in 3D later this year.
The company is at the forefront of 3D development, and Sony Chairman Sir Howard Stringer is on record as saying: "3D is the next great consumer experience and Sony is at the heart of it."
But 3D is not new. The 3D Stereoscope was very popular in Victorian times, and the Viewmaster with rotating 3D discs was invented in the 1930s.
But early 3D films – watched using cheap red and cyan cardboard glasses – were very gimmicky and pretty poor.
So what's changed? Well, according to the Sony engineers, the technology has finally reached a point where 3D films can be made to look really good – Avatar being the obvious case in point.
And digital projection technology has "revolutionised the 3D experience in cinemas", says David Mcintosh, finance director of Sony's Professional division.
It's predicted that there will be 7000 3D-equipped cinemas worldwide by the end of 2010, with 99 new 3D movies due for release by the end of 2012.
"It costs $2500-$3000 to make just one print of a 35mm film," says Mcintosh. "Digital transmission removes that cost so is much more attractive to the studios."
What's more, digital projection means cinemas can simply change the lens on the projector to handle different types of film, rather than having to invest in multiple systems. "Cinemas want a single projector to handle 2K, 4K and 3D films, so a model such as our SXRD 4K digital projector (below) is ideal," explains Philippa Harris, training specialist, Sony Professional.
Sony's SXRD 4K digital projector
"We won't use 'triple-flash' projection in cinemas as that can cause eye strain over the length of a 2-3 hour film," says Harris. "Our system projects a left- and right-eye stream at 2K each, which are then brought together to create a 3D image when the viewer wears a pair of passive 3D glasses."
One of the reasons that cinemas prefer to use passive glasses for 3D rather than the active shutter system used in domestic TV sets is that they're so much cheaper. In fact, a pair of passive specs will cost about one fiftieth the price of an active shutter pair, says David Mcintosh. Given that most manufacturers have said they'll charge around £100 for a pair of active shutter 3D glasses, it's easy to understand why the cinemas might not want to make that kind of investment.
Sony's active shutter 3D glasses
With all the talk of 'active' and 'passive' glasses, you might think there are only two ways to transmit and view a 3D image. Not so: there are in fact five, as outlined here.
This is the older system that uses cardboard glasses with a red lens for the left image and a cyan lens for the right image. This was the system used for Channel 4's recent 3D broadcasts.
2) Linear polarisation
Requires a special display such as a TV with a polarising filter on the front. The left image is vertically polarised and the right image is horizontally polarised. The problem with this system is that the viewer must keep their head absolutely straight, so not practical for use in the home.
3) Circular polarisation
This is the passive glasses system commonly used in cinemas. Odd lines of the image are polarised in a clockwise direction, while even lines are polarised in an anti-clockwise direction. The viewer wears circular polarised glasses.
4) Active LCD
The system being adopted by the majority of TV manufacturers. The viewer wears active glasses which switch at high speed between the left and right eye signals transmitted via infra-red from the TV set. Requires an infra-red decoder and transmitter.
5) Wavelength Multiplex Visualisation, otherwise known as Dolby 3D
Used in some cinemas. A filter wheel is placed in front of the projector, but the glasses are very expensive so not widely adopted.
Of course, the question everyone asks is "when will we have 3D TVs without the need for glasses?" Well, that technology is at least five years off, according to Paul Cameron, training specialist at Sony Professional.
Glasses-less 3D technology in development breaks down into three types: parallex barrier (the system used in current Range Rovers to create a split-screen display on the dashboard, with the driver seeing the sat nav and passenger able to watch a film); lenticular display; and autostereoscopic 3D.
But for now we'll have to stick with glasses if we want to watch 3D.
3D camera rig
However, there are several problems associated with watching 3D using current technologies. One is that around five per cent of the population cannot see 3D because of ophthalmic or cerebral problems. Another is the problem of eye strain, or even feelings of nausea, which can affect some people.
Cameron explains why this can happen: "You need two cameras to film a 3D image: one for the left eye, and one for the right. The two images fool our brain into seeing 3D. Both cameras must be properly aligned and must have perfectly aligned zoom and focus. If one of the cameras is out of alignment, then this breaks the 3D image and can cause eye strain."
It was poor production of early 3D material that led to people suffering headaches and eye strain. To combat this, Sony has developed its own 3D processor box at a cost of nearly £30,000, using the Cell engine found in the PS3, which enables a 'Stereographer' to constantly adjust the image on the fly so everything is correctly aligned. It does all the alignment digitally, rather than in the camera.
Sony's 3D processor box: allows image to be calibrated on the fly
Cameron admits there is a huge onus on the broadcast industry to make sure all 3D content is properly calibrated to prevent eye strain, and there's a considerable amount of training going on right now to try and ensure this happens. "It's an industry-wide problem which will have to be monitored," says Cameron.
Having two cameras does have some advantages, however. Moving the cameras further apart from each other will increase the sense of depth in the picture; conversely, toeing the cameras in towards each other moves the central image back towards the front of the screen.
This allows broadcasters to adjust the 3D image on the fly, so the operator could, for example, focus on a particular player in a football match and bring him to the fore. This means broadcasters have the ability to position people or objects within a 3D scene in a particular way.
A pair of HDC-P1 HD cameras can be used for 3D filming
But there are still plenty of challenges ahead for 3D TV broadcasters. Sky plans to launch its 3D TV channel in April, initially in pubs and clubs around the UK before implementing a domestic service using the current Sky+ HD box later this year.
Darren Long is the Director of Operations for Sky Sports, and the man responsible for bringing Sky 3D TV into our homes. "We trialled side-by-side 3D TV back in 2008 and didn't suffer from tiredness or headaches, so realised that this was something we could do. It's been a journey of learning since then, and we're still learning all the time."
Sky started by filming a Ricky Hatton boxing match back in 2008, and since then has run 3D trials on football, cricket, rugby, tennis and golf.
"Depth and angles are really important when filming in 3D," says Long. "We still don't know exactly what works and what doesn't. We need to employ more stereographers and train our cameramen and directors to film in 3D. Are we experts in 3D yet? No, we're still learning. Often we're working with very large rigs in very confined areas. We are having to retrain everyone, including our graphics suppliers."
"We need to find easier ways of getting the 3D signals back to the OB [outside broadcast] truck. When we filmed Usain Bolt doing a 150m sprint along Deansgate in Manchester last May, we used five cameras on the shoot. In fact, we could have done it with one or two – the rest were superfluous."
Usain Bolt was filmed in 3D doing a 150m sprint in Manchester
"What we have learnt is that angles give you better depth. When we filmed the Arsenal vs Manchester United match at the Emirates Stadium in January, we had six cameras, including one behind the goal. We needed more lower angle cameras to get the best 3D effect, but the stadium told us where we could put them, so we had no choice over positioning. That is something we will have to look into."
Long believes 3D will work well with most sports, and in preparation for this Sony is helping build the first dedicated 3D outside broadcast truck for Sky, at a cost of around £4.5m, in conjunction with independent TV production company Telegenic. The wiring alone took two months, with 70,000 metres of cabling inside the truck – enough to loop around a football pitch 200 times! A second 3D OB truck has been commissioned for delivery this July.
Exterior of the Sony/Telegenic/Sky 3D outside broadcast truck
Interior: looks as if NASA could launch a Space Shuttle from here
With the World Cup kicking off on June 11th, and key matches in South Africa being filmed in 3D, the big TV manufacturers hope this will be the perfect springboard for launching 3D TV in the home.
But Sony's Paul Cameron sounds a note of caution: "I don't think the World Cup will be the first 'big thing' for 3D – it's too soon. I think it will be the Olympics in 2010 when we see the big breakthrough."
That won't deter the likes of Sony, Samsung, Panasonic and LG pushing 3D TVs for all they're worth over the summer. We've already had a flurry of product launches, with models promised from March onwards.
Nick Sharples, director of corporate communications at Sony Europe, says: "We believe 2010 will be the tipping point when 3D TV enters the home, although it won't be an explosion. Initially we expect to sell 3D TV to early adopters, who will see it as a status symbol." Sony predicts that 3D sets will account for around 10 per cent of its TV sales by the end of 2011.
Will you be tempted to buy 3D TV?
Although 3D Blu-ray discs and Sky 3D should work on all forthcoming 3D TVs, each manufacturer is developing it own bespoke 3D active shutter glasses. So Sony's 3D glasses won't work with Panasonic 3D TVs, for example.
"The Consumer Electronics Association (CEA) in America has started discussions on a generic standard for active-shutter 3D glasses, so it could happen," says Sharples.
But, as yet, the Glasses Standardisation Working Group of the CEA hasn't solved the problem, so for now you'll have to buy the 3D glasses specifically designed for that brand of 3D TV.
No standardisation for active shutter 3D glasses
Another fascinating fact that emerged during the day is that there's a drop of around 50 per cent in high-definition quality when viewing in 3D. "We have found that viewers will accept a drop in HD quality for 3D," says Cameron. "Although we're using Full HD, 1080p transmission for 3D, there's a 5-10 per cent drop in HD quality at the production end, and a 50 per cent drop at the viewing end."
I bet that's something the TV manufacturers aren't going to shout about. And of course if you want to watch 3D in the home, you'll have to buy a new 3D-enabled TV and 3D-enabled Blu-ray player so, initially at least, it will be a big investment.
With that in mind, Sony has another interesting trick up its sleeve. It's working on a system to "upconvert" a standard 2D broadcast to 3D. What we saw in Basingstoke was three cameras being used to capture an entire football pitch (each camera films one third of the pitch). The three images are then merged together to give a widescreen view of the entire pitch.
Simulated 3D from a 2D broadcast
A Tri-sight camera system then runs three HD feeds into a Cell processor which can then output a simulated 3D feed to the screen. What the processor does, in simple terms, is take the existing right-eye view and recreates a simulated left-eye view. Look at the screen without 3D glasses on and you'll see each player in double; put the glasses on and you get the simulated 3D effect.
'Proper' 3D is better, particularly for close-ups, but the simulated 3D is surprisingly convincing for the overall pitch view and long shots.
The system can also track individual players on the pitch and be used to recreate on-screen graphics showing their movements, where they run and the offside line at various stages during the match.
This pseudo-3D system is still at the early R&D stage, but Sony hopes to have it ready for use in live matches later this year.
Whichever way you look at it, 2010 promises to be a fascinating year for the development of 3D TV and film technology.
Look out for our special Future of TV supplement, on sale with the May issue of What Hi-Fi? Sound and Vision from April 7th.