Jon Bentley's verdict on buying a HDR TV
HDR (or High Dynamic Range) TV is television as we know it but with a much wider range of colour and contrast. Pictures look more like real life with extra detail in the dark areas and the highlights. It’s TV to a new, much higher visual standard and, having reviewed it in this week’s programme, I think it’s a very good thing, which will greatly enhance our viewing pleasure.
The development comes with some impressive statistics. Whereas conventional TVs can process an 8-bit colour signal, meaning they can theoretically display around 17 million colours, HDR TVs are at least 10-bit, which means they can show over a billion. Though this might seem like an impossibly large number of colours, the difference really does help show gradations in tone and brightness more accurately.
Then there are nits. A nit is a standard measure of luminance, equivalent to a candela per square metre. Normal TVs have a maximum brightness of around 400 nits but HDR TVs have to achieve 540 nits and many deliver far more.
In practice, one doesn’t have to worry about the figures, just enjoy the improved pictures. But there will be quite a few hurdles to overcome before all our TV watching is HDR.
For a start everything in the production chain has to be HDR compliant. That means better cameras, editing software and transmission. It will be a while before most content is shot and edited to these exacting standards.
Netflix and Amazon are showing some HDR content but they’re in the minority. Major UK broadcasters aren’t likely to be showing HDR for a while yet. And the bandwidth required to stream the higher quality footage remains an obstacle to getting HDR into the home for some.
There are also different HDR standards fighting it out, mainly HDR-10, which is open and has been adopted by most TV manufacturers, and Dolby Vision, which is more exacting and proprietary. Broadcasters like the BBC and Japan’s NHK are developing their own standards too. And there’s still a debate about what metadata needs to be transmitted along with the pictures to tell your HDR TV how best to display the footage.
But in the meantime, if you’re about to buy a new TV, don’t worry; choosing an HDR one will mean you’re getting the very best picture quality available, and visual standards vastly better than TVs of just a few years ago.