So far no one has done a truly objective look at what HDR content truly means. Therefore, I did some tests last night to demonstrate what “HDR” truly means with respect to the new UHD HDR Blu ray format.
The first thing I want to demonstrate is that the actual HDR content contains additional data or image detail that is not in the standard 1080p Blu ray. This data can be displayed by ANY TV whether it has the HDMI 2.0a capabilities that allow it to read the HDR header information or not.
The images below show the maximum amount of shadow detail you can extract from a scene in the movie the Martian(Approximately 59:45 into the movie). With the 1080p Blu ray you can see that half of Mars is literally clipped into Black. If you adjust the settings here the black background will bloom above zero black but it will not show any more useful detail of the portion that is in the shadow.
1080p Blu ray
UHD HDR Blu ray
With the UHD HDR Blu ray you can see how adjusting the settings can extract that extra detail that does not exist on the 1080p Blu ray. All of these images come from a Vizio M80 TV which is not an HDR TV because it lacks the ability to read the HDR headers and it lacks the Wide Color Gamut capabilities. However, it is clear that it can in fact show all of the extra shadow details that the UHD HDR Blu ray contains.
Now this is not to say that non HDR TVs are the equivalent of true HDR TVs. They are not. However, most people here have not been stating the differences correctly.
With Non HDR TVs they can take advantage of the extra shadow and highlight detail that is contained on the disc up to the capabilities of their backlight. However, non HDR TVs require extensive manual settings adjustments in order to display the content properly. With TVs that have HDMI 2.0a capabilities the TV will read the HDR header information and make these adjustments automatically behind the scenes. The average person would never invest the time into manually adjusting the settings like I have done to produce these results with a non HDR TV. That is a gigantic plus for any TV that has HDMI 2.0 capabilities when using HDR content.
In addition my Vizio M-series TVs lack the wide color gamut capabilities that SOME HDR TVs have. There is literally no settings adjustment I can make to show the colors that a Wide Color Gamut(WCG) HDR TV can display. That is another very significant difference.
The issue is that some TVs that are called HDR TVs because they have the HDMI 2.0a capabilities to read the HDR header information lack the Wide Color Gamut capabilities. That really limits the HDR benefits of those so called “HDR Lite” TVs. Some examples of these TVs that lack Wide Color Gamut capabilities are the 2015 Samsung JU series(JU7500,JU7100,JU6700…etc) and the 2015 Sony X830c and X810c TVs
With an HDR Lite TV you get the automatic settings adjustments over a non HDR TV but that is just about it. Their color spectrum is slightly broader than something like the non HDR Vizio M-series but not significantly broader.
Then finally we have Premium HDR TVs that have HDMI 2.0 capabilities with VERY broad Color Spectrums and also very bright backlights with darker black capabilities. Their bright back lights with great local dimming capabilities allow them to display a broader dynamic range than lesser TVs but that doesn’t mean they show any more shadow or highlight detail than even non HDR TVs.
Dynamic range is simply the range from the darkest black to the brightest white that the TV can display. It is a misconception that the content controls this dynamic range. The HDR Blu ray doesn’t magically make your TV display a darker black. The content contains data that represents “Zero Black”. If your TV is properly mapping its “Zero Black” value to match the content the TV will show its minimum Black level whether the content is HDR or not.
What the brighter back light does is allow your TV to display a bigger difference between its true black and true white. That difference is often perceived as “Better Contrast” and is often very desirable.
At the moment virtually all of the UHD Blu rays are produced from a 1080p source so unfortunately none of the extra resolution and detail of UHD Blu rays can be realized for an entire movie yet. That will change over the next few weeks when true “4K sourced” UHD Blu rays are released. Hopefully, over time more and more discs will be sourced from true 4K sources so all 4K TVs can take advantage of that extra resolution.
I think the most important question you should ask yourself when trying to decide what TV to get for HDR content is “Do you want to pay extra for Wide Gamut Color capabilities or not”. The difference in color capabilities between these TVs is very significant and unlike resolution differences it can be perceived no matter how far you sit from the TV. It can even improve the perceived effect of off axis color loss which is a big benefit for some people.
Also please note that “Quantum Dot” technology is not an absolute requirement for Wide Color Gamut capabilities. Some TVs can get a wider color range without that technology. It is traditionally much better if it does have it but it doesn’t necessarily mean that if it doesn’t have “Quantum Dot” technology that it is not a WCG TV.
I hope this write-up helps you in making your TV purchase.