Many new TVs, phones, tablets, and other screen devices support HDR. Seen as a way to achieve more vivid colors and a better picture, HDR formats are becoming an increasingly important aspect of any new TV purchase. But what exactly is HDR? And what is the difference between HDR formats?
HDR essentially lets you get brighter images and more vibrant colors, as long as the screen and content support the technology. From HDR 10 to Dolby Vision, here’s everything you need to know about HDR.
What does HDR mean?
HDR stands for “High Dynamic Range”. The term basically refers to a technology that allows displays to display a greater dynamic range than in “SDR” or “Standard Dynamic Range”. But what is dynamic range? It’s essentially the difference between the blackest blacks and the whitest whites a screen is capable of producing.
There are good reasons why you might want more dynamic range in an image. Higher dynamic range essentially helps you see better details in brighter images, making them look more realistic. Non-HDR images can look dull and flat compared to real life, while HDR video approximates real-world brightness and color.
Of course, just as HDR was born out of advances in technology, newer and higher quality HDR formats are likely to appear as televisions and displays become more capable. Over time, screens have become brighter and brighter, allowing for more realistic images. The idea isn’t just that you want infinite brightness – after all, at some point it would hurt your eyes. Instead, brighter screens can show more detail in bright sections of an image. The same goes for dark sections of an image – the darker an image can get, the more detail you’ll get in shadows and other dark images. We probably won’t get much darker than OLED and Micro-LED screens, which can display true black by turning off sections of the screen.
Brightness aside, HDR formats can also display more colors, which also results in a more detailed image that looks more like real life.
What is HDR10?
There are a number of different types of HDR you’ll find on screens these days. Popular ones include HDR10, HDR10+, Dolby Vision, and HLG. The most common of these is HDR10.
There are a number of reasons why HDR10 is so popular. For starters, it’s an open standard and is used by a huge range of streaming services, including Netflix, Disney+, Apple TV+, and more.
HDR10 supports 10-bit color depth, which means it can support many more colors than 8-bit SDR images. In fact, while 8-bit images can support nearly 17 million colors, 10-bit images can support over a billion colors. Some TVs support 12-bit color depth, which means they can display 68 billion colors.
HDR10 is rated to produce 1,000 nits of brightness, which is part of why the standard is getting a bit old. Most high-end TVs these days can produce well over 1,000 nits of brightness.
HDR10 uses something called “static metadata”. This basically means that a set of metadata is sent to your screen at the start of a scene. The advantage of this is that it takes less bandwidth than a format like Dolby Vision, which can send metadata frame by frame.
What is HDR 10+?
Dolby Vision may be better than HDR10, but since it’s a proprietary standard, it costs manufacturers licensing fees. This has led to the rise of HDR10+.
HDR10+ not working enough achieve the technical ambitions of Dolby Vision, but it thrives on HDR10. It retains 10-bit color support but increases peak brightness to 4,000 nits.
Many TV manufacturers make HDR10+ compatible TVs, but content and other devices are a bit scarce. The goal is for it to become more popular over time and compete more with Dolby Vision.
What is Dolby Vision?
Dolby Vision is a format developed by Dolby Labs. Of course, since it’s a proprietary format, Dolby Labs also licenses it. In other words, it’s not an open standard like HDR10, and because of that, not all TVs support Dolby Vision. However, more and more content supports it, including on services like Netflix, Apple TV+, Disney+, and more.
Dolby Vision offers a number of clear advantages over other HDR formats. Namely, the standard supports 12-bit color and a theoretical maximum brightness of 10,000 nits. There isn’t really any content that can actually hit these color or brightness limits, which means Dolby Vision is much more scalable than other HDR standards. Eventually, the technology will likely overtake Dolby Vision, but it may take a while before that happens.
Unlike HDR10, Dolby Vision uses “dynamic metadata”. This means that every frame in a video can be edited. The downside to this is the fact that it uses a lot more bandwidth, but it ends up being much better than HDR10 content.
What is HLG?
HLG, or Hybrid Log-Gamma, is a little different from other HDR standards. For starters, it was developed specifically for broadcast signals, by the BBC and NHK, a Japanese broadcaster. Unlike other HDR formats, HLG does not use metadata to tell a TV how to display an image. Instead, HLG takes an SDR signal and adds an HDR information layer on top of it. This means that TVs that do not support HLG will just display the image in normal SDR. And, TVs that support it will gain additional insight into displaying a brighter, more vibrant picture.
There are a few drawbacks to this approach. HLG can make images brighter and more vibrant, but it can’t do much about an image’s black levels – so you won’t really get better detail in shadows and night scenes.
HLG is still in its infancy and therefore there is not much HLG content. We’ll have to wait and see if that changes over time.
Is HDR only for 4K?
No. In fact, the two are not really related. 4K refers to the resolution of a TV, while HDR refers to the range of colors offered by the display. Most 4K TVs support some sort of HDR, but some 1080p TVs also support HDR.
How to watch HDR
If you want to enjoy HDR content, you’ll need a few things. To get started, you’ll need a TV that supports an HDR format – and they’re not compatible with each other. That means you won’t get the benefits of Dolby Vision on a TV that only supports HDR10+. You will also need to find content available in this format. There’s a lot of content in Dolby Vision and HDR10+ these days, but not everything. Most streaming services label the formats you can watch in.
If you’re using a streaming device, like an Apple TV or Roku, that device will also need to support the format.