Upgrading to an Ultra HD TV
Here’s What You Should Know
It’s winter again and with the falling temperatures it’s time to catch up on all your favorite shows and movies. Seems like as good an excuse as any to upgrade that old flat screen to a shiny new 4K model doesn’t it? Most people think this should be pretty straightforward – just head to your nearest dealer and buy whatever’s on sale. After all, all you really want to do is watch zombies, right? This approach is fine if good enough will do. However, if you really want to maximize performance and make those zombies look their best, there is much more to consider.
As you search for the perfect set, you’ll encounter a plethora of manufactures, models, features and, worst of all, acronyms - lots of acronyms. HDTV, UHDTV, HDMI, HDCP, HDR, fps, LCD, LED, OLED, QD and Gbps are the biggies you’ll encounter on this particular venture. To make sense of it all, you can either go back to school for an electrical engineering degree or choose an easier path and just keep reading.
HDTV should be an easy one. High Definition TV has been with us for a long time now. This is what you’re trying to upgrade from so you definitely don’t want to buy another one. Ultra-High Definition TV or UHDTV is what you’re really after. This is the so called “4K” TV you’ve been hearing about. These sets have four times more pixels than HDTV and consequently give you a much clearer and sharper image.
So far, so good, right? LCD, LED, OLED and QD are all about the fundamental technology the TV uses to produce the image you see on the screen. LCD stands for Liquid Crystal Display, QD for Quantum Dot, LED for Light Emitting Diode and OLED is an Organic Light Emitting Diode. Details of how these technologies work is well beyond the scope of this article, but the main thing to know is that out of all these different technologies OLED will give you the best results, followed by the quantum dot displays. Quantum dot technology is, in fact, an enhancement to standard liquid crystal displays that increases their performance to near OLED levels.
Now comes the fun stuff. High-Definition Multi Media Interface or HDMI is the name of the connectors used to link together sources, receivers and displays. In the TV world, HDMI version 2.0a is the one to get. It’s capable of high speed data transfers up to 18 Giga bits per second (Gbps) and is high dynamic range (HDR) compatible. HDR (or HDR10 as it’s formally known) is a technology that allows a display to dramatically increase its contrast ratio. This is the contrast between the brightest and darkest image the display can produce. HDR provides a much more accurate and realistic viewing experience.
The HDMI 2.0a version also enables video signals with a greater number of frames per second (fps). In fact, up to 60 fps is now supported. This is twice the frame rate of regular TV and 2.5 times greater than the typical 24 fps frame rate used in the film industry. The higher frame rate leads to smoother, less jagged motion. Finally, thanks to a 10 bit colour gamut, HDMI 2.0a supports a very rich colour palette even at 4K resolutions. It can actually support more than 1 billion colours.
High-bandwidth Digital Content Protection or HDCP is the copy protection scheme used to prevent piracy. You really need to choose components that support version 2.2 or higher. Earlier versions will not allow you to watch 4K content. UHD Blu-ray players for example, absolutely require it and simply will not work without it.
As you may have realized by now, there’s a lot to consider if you’re looking for a top notch TV for your living room or home theater. You need to think about which technology it’s based on, which version of HDMI it supports, its maximum resolution, its highest frame rate, its colour gamut, HDCP and whether or not it supports HDR. It’s possible to dive even deeper into the abyss and look into
motion resolution or the colour compression formats it supports. Seems pretty daunting doesn’t it?
Fortunately, a group of industry heavy hitters have formed the UHD Alliance. The members include hardware manufactures like Sony, Samsung, Panasonic, LG and others but it also includes content creators like DreamWorks, Paramount, Universal, Disney, 20th Century Fox and Netflix. Even content distributors like Rogers and audio companies like DTS, Dolby and THX have gotten involved. There are currently 35 corporations in the alliance. The group’s goal is to facilitate the consumer’s selection process to provide “a seamless, integrated and high-quality UHD ecosystem from endto-end” (source: UHD Alliance home page: http://www.uhdalliance.org/). This will involve both certified content and hardware. If they meet all the necessary requirements, they will be allowed to bear the “UltraHD Premium” logo.
The certification is largely aimed at eliminating the consumer’s burden of having to understand all of the technical mumbo jumbo necessary to make the best possible choices in entertainment electronics. In its current iteration, the UltraHD Premium specs stand as follows: • Minimum resolution of 3840 X 2160 (aka UHD) • Inputs must accept a BT.2020 colour representation • 10 bit colour depth ( more than 1 billion colours) • Must be able to display more than 90% of the DCI-P3 colour gamut • Must comply with the SMPTE ST2084 EOTF High Dynamic Range (HDR) spec • Display must be capable of at least 0.05 to more than 1000 nits of light output (20,000:1 contrast ratio) OR • It must be capable of a least .0005 to more than 540 nits of light output (1,080,000:1 contrast ratio) From these specs we can see that the Digital Cinema Initiatives (DCI) 4K resolution of 4096 × 2160 used in Sony’s 4K projectors would also qualify as it exceeds UHD’s 3840 X 2160 resolution. The required colour palette is far broader than the 8 bit colour we’re used to with Blu-ray players, which are only capable of 16,777,216 colours. This may sound like a lot, but is actually 64 times less than the UltraHD Premium standard. The recently released UHD Blu-ray players also support the same 10 bit colour gamut.
The two different contrast ratios are tailored to different display technologies. The first one is primarily aimed at LCDbased displays, while the second is aimed at OLED displays. The far wider contrast ratios associated with OLED clearly suggests that this technology is capable of fabulous blacks and awesome dynamic range. The LCD-based sets, with their greater output, would perform a little better in rooms with poor light control but if you’re looking for the best possible performance in a darkened room, the OLED wins hands down.
So now you’re all set right? Not so fast. Although the UHD Alliance’s efforts to make things simple and easy are commendable, there are some noteworthy issues. Sony, for example, who is one of the alliance’s big members has chosen not to use the UltraHD Premium logo for its own products. Instead, it uses its own internal standard called “4K HDR” even though their products do comply with UltraHD Premium specifications. Samsung and Panasonic, on the other hand, have embraced the new logo.
The bigger issue is VIZIO. They don’t agree at all with the new standard, sighting that the specification lacks important details on exactly how to measure various display characteristics like light output, peak brightness and contrast ratio. They claim that there are no set limits for undesirable phenomena, such as haloing artifacts and blooming, which adversely affect dynamic range and picture quality. This could lead to the certification of displays that really don’t deserve it or the omission of sets that do. This is clearly not a desirable situation.
VIZIO even accused the UHD Alliance of creating specifications that favour certain hardware platforms to the detriment of others. For example, VIZIO’s reference series sets are spectacular performers but don’t technically meet the UltraHD Premium spec. Their contrast ratios are 800,000:1 which is phenomenal but they don’t fall neatly into either of UltraHD Premium’s two contrast ratio categories. As a result, VIZIO has chosen to pursue a competing HDR spec called Dolby Vision. They feel that Dolby Vision is a superior and more robust specification. It’s a little ironic that Dolby is also a member of the UHD Alliance.
Dolby Vision is indeed superior to HDR10 in several ways. For example, Dolby Vision sets its current brightness target at 4,000 nits with a contrast ratio of 2,000,000:1. In the future, the brightness target will increase to 10,000 nits. Furthermore, Dolby Vision allows a colour depth of up to 12 bits which represents more than 68.7 billion colours. Finally, Dolby’s technology also allows contrast ratio optimization from scene to scene within a movie whereas HDR10’s tweaks are applied across the entire film.
In addition to VIZIO, LG, Sharp, TCL and Philips are also pursuing the Dolby Vision spec on at least some of their models. Studios like 20th Century Fox, Paramount, Sony Pictures, Disney and Warner Brothers have also announced support for Dolby’s format. So unlike VIZIO, some manufacturers and studios have clearly chosen to embrace both technologies.
Unfortunately, it looks like we may be heading toward a minor HDR format war. On the bright side, both can coexist peacefully. In the future, we may be seeing TVs, UHD Blu-rays and players sporting both logos. For the moment, UltraHD Premium has greater market penetration but who knows what will happen in the long term. Regardless of which option you choose, both will have very real benefits. And those zombies will look better than ever.