Television tech explained

RECENT ADVANCES IN TV TECHNOLOGY HAVE SPAWNED A HOST OF NEW ACRONYMS AND CONFUSING FORMATS. WE’LL EXPLAIN WHAT THEY ALL MEAN.

TELEVISION TECHNOLOGY HAS come a long way in a short time, and has brought with it a whole raft of abbreviations, acronyms and similar sounding names. These technologies often have several variants, each with their own acronym. So, we attempt to explain the difference between 4K, UHD, OLED, QLED, HDR (and variants thereof).

4K

With the increasing availability and affordability of TV sets and all-important content, 4K (also known as Ultra HD, 4K Ultra HD, UHD) technology is here to stay – until it’s leapfrogged by 8K.

WHAT IS 4K ULTRA HD?

Officially, 4K resolution is 4096 x 2160 pixels. However, in order to shoehorn this into a 16:9 format, it was altered to 3840 x 2160 – four times the number of pixels on a Full HD screen (1920 x 1080). To play 4K Ultra HD you will need a compatible TV, source and some content.

There are lots of 4K TVs on the market, a few 4K projectors and even 4K phones. As for a source – Amazon, Netflix and YouTube all offer streaming 4K content, including on 4K streaming boxes such as the Amazon Fire TV 4K and Google Chromecast Ultra. The Apple TV 4K box can stream 4K HDR content (HDR10 and Dolby Vision) from iTunes.

HOW CAN YOU WATCH 4K?

If you want to play discs, you need a 4K Blu-ray player, such as the Sony UBP-X800 or Oppo UDP-203, and some Ultra HD Blu-ray discs. If you’re streaming content, you’ll need something like an Nvidia Shield TV or similar device.

CAN YOU STREAM 4K VIDEO?

Netflix 4K streaming arrived in 2014, with House of Cards: Season 2. There are now over 100 titles, with more content being added all the time. To watch it, you will need a 4K TV that supports the HEVC codec, which is most 4K TVs since 2016.

Amazon’s 4K content comprises TV shows, such as The Grand Tour, and The Man In The High Castle. YouTube also has a selection of 4K videos, using the VP9 codec developed by Google. Make sure your TV or monitor supports VP9.

AND 4K MEDIA STREAMERS?

The Amazon 4K Fire TV box delivers Ultra HD content from Amazon’s own library on Prime Video and from Netflix. The Roku Streaming Stick+ offers a similar proposition, while Google’s Chromecast Ultra and Sony’s PS4 Pro console offer 4K content from Netflix and YouTube. The Apple TV 4K can stream Ultra HD content from Apple’s iTunes store. The Xbox One X also makes a fine streamer and player.

WHAT ABOUT 4K BROADCASTS?

So far in Australia 4K broadcasts are pretty much non-existent. It’s been tested, but none of the free-to-air channels are offering it. In the UK, however...

In December 2017, the BBC launched a 30-day trial stream of its Blue Planet II series in 4K (and HDR) through the BBC iPlayer. This year, a 4K live rugby league match on iPlayer was followed by a 4K broadcast of the 2018 FA Cup final.

This culminated in a 4K trial, using iPlayer, for the 2018 World Cup, where 29 games were broadcast in Ultra HD on compatible TVs and set-top boxes. The BBC followed this up with another 4K trial for its Wimbledon 2018 coverage.

ULTRA HD BLU-RAY DISCS

UHD Blu-ray has picked up steam, with most major Hollywood studios backing the format. Over 100 titles (and growing) from Warner Bros, 20th Century Fox and Sony Pictures are now available.

HDR

High Dynamic Range (HDR) is the most important buzzword in TV now. But with manufacturers developing different varieties, it can be hard to keep track.

WHAT IS HDR?

Originating in photography, HDR refers to a technique to heighten a picture’s dynamic range – the contrast between the brightest whites and the darkest blacks. The higher the dynamic range, the closer an image gets to real life.

As TVs have become more capable, they can go a lot brighter, but the tech isn’t about brightness, it’s about widening the range to display finer increments of shading and get more details in the shadows and highlights.

There are four main varieties of HDR: HDR10, HDR10+, HLG and Dolby Vision.

WHAT IS HDR10?

HDR10 is the original and most common form of HDR. All current 4K TVs feature HDR10 and so should be compatible with the most widely available 4K Blu-ray discs, 4K players and 4K streaming content.

WHAT IS HDR10+?

Samsung has developed its own standard: HDR10+, using dynamic metadata to boost HDR images frame-by-frame. The company’s 2018 line-up of TVs supports the HDR10+ format but, since it is a direct rival, none of Samsung’s TVs supports Dolby Vision.

The first Ultra HD Blu-ray discs with HDR10+ are due out later this year, and will be 20th Century Fox and Warner Bros releases. Amazon Prime Video was the first content provider to announce HDR10+ support, and will be streaming over 100 shows in HDR10+ on Samsung’s 4K and QLED TVs – but only in the US.

WHAT IS HLG?

The result of a research project between the BBC and Japanese broadcaster NHK, Hybrid Log Gamma (HLG) is potentially the most important HDR format.

It takes standard dynamic range and HDR images and combines them into one feed, with HLG-compatible 4K TVs able to decode and show HDR images.

Most big manufacturers confirmed HLG-ready sets for 2018 and 2017, and content arrived in the form of Blue Planet II – released in full 4K and HLG on BBC iPlayer in 2017. The 2018 World Cup and Wimbledon trials were streamed live in 4K and HLG on the iPlayer.

WHAT IS DOLBY VISION?

Designed for cinemas, Dolby Vision differs from HDR10 in that, while the latter applies its parameters scene-by-scene, Dolby Vision allows for dynamic metadata to be added on a frame-by-frame basis, giving an improved image.

Both HDR10 and Dolby Vision can feature on the same TVs and discs. You will need a Dolby Vision-compatible disc, Blu-ray player and TV before you can enjoy the technology at home.

On the hardware side, LG has been the format’s biggest adopter, with its 2018 OLED TVs supporting Dolby Vision.

HOW CAN YOU WATCH HDR?

You will need a compatible display – a TV, projector or smartphone. Most new 4K TVs support the format as standard.

You will also need an Ultra HD Blu-ray player, such as the Cambridge CXUHD or Oppo UDP-203. Microsoft’s Xbox One S and Xbox One X also play 4K Blu-rays and include HDR10 support.

Alternatively, you can stream HDR content via Netflix or Amazon Prime

Video – both services support HDR10 and Dolby Vision (Amazon’s HDR10+ content is available only in the US). This can be done through a compatible app on your TV or streaming box, such as the Amazon Fire TV or Apple TV 4K.

WHAT HDR CONTENT IS THERE?

Amazon Prime Video was the first to stream HDR content, but Netflix has a large library, most of which is also in 4K. Apple is about to stream 4K HDR films through iTunes. The UHD Blu-ray format includes HDR10 in its base specification and supports Dolby Vision on select titles. HDR10+ titles should be available at the end of the year. Over 100 4K Blu-ray discs with HDR are on sale now.

THE FUTURE OF HDR

The combination of 4K and HDR means a super-sharp, dynamic picture and a clear step-up from Full HD. Potential issues are the different variations of HDR and the need to ensure your TV is future-proofed – there is a bubbling format war between HDR10+ and Dolby Vision.

OLED

The first Organic Light-Emitting Diode (OLED) TVs, from LG and Samsung, hit the shelves in 2013, giving a glimpse of its ultra-dark black tones, super-punchy contrast and slimline design. Soon after, Samsung ditched OLED for QLED – a completely different TV technology.

WHAT IS OLED?

OLED makes it possible to reach dark black levels from ultra-thin screens. It works with a carbon-based film between two conductors, which emits light when an electrical current is passed through it.

Unlike a Liquid Crystal Display (LCD) panel, which requires a backlight to light up the crystals, this takes place in every pixel of an OLED display. With LCD, you can’t achieve true blacks as the backlight affects neighbouring pixels. As OLED pixels generate their own light, they become pitch-black when turned off.

OLED also includes an additional white pixel alongside the usual red, green and blue sub-pixels, which delivers more varied and accurate colours.

THE ADVANTAGES OF OLED TV?

OLED sets are lighter and thinner than LCDs, as they don’t require a backlight. Each pixel can be turned off individually, so OLED TVs deliver absolute black and stronger contrast ratio – the holy grail for AV purists. Because of their thinness, manufacturers can curve, bend and roll OLED panels up. LG developed a rollable 77in screen, not forgetting the ultra-thin ‘Wallpaper’ range, which sticks to a wall. And the disadvantages? OLED is expensive to produce and so TV sets are expensive. Prices have come down, though.

AND WHAT IS QLED?

Currently, Quantum-dot Light Emitting Diode (QLED) is a refinement of LCD technology where a Quantum dot layer is placed between the backlight and the LCD panel. The Quantum dot particles emit light of a specific colour when the backlight shines on them – bigger particles emit red light and the smaller ones blue light, for instance.

Despite being easier and cheaper to manufacture, QLED sets have, until now, been almost as expensive as their OLED equivalents. But with further development, we could soon reach a point where the Quantum dot particles can generate their own light – that’s when OLED technology will really have something to worry about.

THE COMBINATION OF 4K AND HDR MEANS A SUPER-SHARP, DYNAMIC PICTURE AND A STEP-UP FROM FULL HD. POTENTIAL ISSUES INCLUDE A BUBBLING FORMAT WAR BETWEEN HDR10+ AND DOLBY VISION