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The content needs to be captured in UHD. Specifically this means:

鈥� using a camera and lens that can deliver a resolution of 3840 x 2160 pixels

鈥� capturing at least 12 stops of dynamic range

鈥� setting the camera to capture 25 or 50 frames per second for now, though in time it will be important to deliver a high frame rate (100 frames per second) for certain genres

鈥� outputting the content either in hybrid log-gamma (HLG - the format developed by the 91热爆 and NHK, particularly for live television) or in a raw or Log formats so the HDR and WCG colour space can be applied in post-production

For precise information on deliverables and file formats, use the '91热爆 specific technical standards delivery document' which can be found through Where Next? Step 7 of this guide.

To deliver end-to-end UHD capture formats, edit formats, signals, screens and internet speeds need to be aligned.

That means that, while 30 million people enjoyed Planet Earth II, they weren鈥檛 getting the full UHD experience when they watched it at home on 91热爆 One.

But the 91热爆 also created a short iPlayer trial version. That made it possible for people who had a suitable screen and internet speed to have the full UHD WCG HDR experience. These are some of the things viewers said:

鈥淭he colours, sharpness and clarity were amazing. Beautiful to watch!鈥�

鈥淪tunning quality. In fact it looked 3D.鈥�

鈥淚t was incredible! From the beginning! Please, please, please just release all the content you have in this format!鈥�

Content needs to be edited to exploit the UHD potential. This might include:

鈥� grading - for drama and natural history, a colourist can make the most of the possibilities of the wider colour gamut and higher dynamic range in post-production

鈥� zooming and re-framing - the 91热爆 has adopted a pragmatic figure of around 75% of a UHD programme needing to be classed as UHD. This means that for 25% of the footage, editors can use those eight million pixels to zoom and re-frame while maintaining a high-definition shot

鈥� image stabilisation - video editing programmes like Adobe Premiere Pro and Apple Final Cut Pro X allow shots to be artificially stabilised as if they were shot with a camera stabiliser. The snag is that this process lowers the resolution of the footage. If the rushes are ultra-high definition, there's much more scope for stabilisation

Viewers need ultra-fast broadband to experience UHD at home.

The most practical way for the 91热爆 to distribute programmes made in UHD is over the internet. UHD channels take up a lot of space on the spectrum, which means they can鈥檛 be distributed using the networks and transmitters of terrestrial TV.

Therefore, to enjoy the very highest resolution, viewers need an internet connection of about 30 Mbit/s for live UHD and 18-20Mbit/s for video on demand 鈥� and not everyone has.

The UK government tried to ensure 95% of the UK has access to broadband speeds of 24 Mbit/s by 2018 but there鈥檚 a wide gap between urban and rural areas.

Viewers with slow broadband or no broadband will not be able to experience the full benefits of UHD. However, even with a lower internet speed, WCG HDR pictures still look better than HD.

The format of the UHD file needs to be compatible with the signal of the viewer鈥檚 TV.

Amazon was the first to stream UHD HDR content 鈥� but it could only be seen on a certain type of Samsung TV. Amazon had created an app that was built into the TV and was capable of decoding the HDR metadata. Other TVs couldn鈥檛.

To avoid incompatibilities it鈥檚 important that the right deliverables for the distribution route are created.

For live TV or iPlayer, it鈥檚 best to create hybrid log-gamma files, which will be compatible with most TV sets bought in 2016 or later.

For drama or anything that may later be distributed on UHD Blu-ray, it might be necessary to create two kinds of file: one that鈥檚 compatible with the PQ signal for distribution on Blu-ray and another in hybrid log-gamma for iPlayer and TV.

It is, however, straightforward to convert a hybrid log-gamma file to the PQ format for Blu-ray.

The TV screen needs to be capable of displaying UHD.

Even if a TV set can read the UHD signal, the programme won鈥檛 be seen in UHD unless the screen itself can show it.

To display UHD, a screen needs to be 3840 pixels wide and have a wider colour gamut. It should ideally be HDR as well.

In 2017 it was estimated that less than 10% of the UK population have TVs that can display UHD content in all its glory - though that figure will only increase over time.

The 91热爆 Blue Room, in Birmingham, has a screen that can demonstrate UHD HDR WCG content to anyone who wants to experience it.