HDR on Your TV: What the Format Labels Mean and What to Enable
HDR — high dynamic range — is both a display capability and a content format, and the two don't always match. A television that supports four HDR formats will not improve the picture quality of content that was mastered without HDR. A television with one HDR format may produce excellent results with content it handles well and poor results with content it doesn't support.
Understanding the formats, what they require from your display and what they actually do to the image helps navigate the settings options that most manufacturer menus don't explain.
What HDR actually is
Standard dynamic range (SDR) content is mastered to a reference display brightness of 100 nits — a brightness level that most televisions can exceed significantly. HDR content is mastered at higher reference points, typically 1000–4000 nits for HDR10, and carries metadata that describes how the image should be mapped to displays of varying capability.
The practical benefit of HDR is not simply a brighter image. It is a wider luminance range within the same frame — the ability to have a bright specular highlight and a visible shadow in the same shot without one or the other clipping. This is closer to the way the eye perceives a real scene.
Whether your television can actually deliver this benefit depends on its peak brightness capability. A display that can achieve 400 nits peak is technically HDR-capable but will produce noticeably different results from one that achieves 1500 nits on the same HDR content.
HDR10
HDR10 is the baseline HDR format, supported by every HDR-capable television. It uses static metadata — meaning the brightness and colour information that describes how to display the content is set once for the entire film or programme, rather than adjusted scene by scene.
The static nature of HDR10 metadata is its primary limitation. A mastering engineer sets the metadata for the overall programme, but individual scenes may be significantly darker or brighter than the average. The display applies the same tone mapping approach throughout, which can result in some scenes looking excellent and others looking clipped or crushed depending on the display's capabilities and the content's brightness range.
Dolby Vision
Dolby Vision uses dynamic metadata — the tone mapping information is updated per scene or per frame. This allows the display to apply different brightness and colour adjustments to each scene based on its specific content, rather than applying a single average setting throughout.
The result on capable displays is consistently more accurate rendering across the full brightness range of a programme. The limitation is that Dolby Vision is a licensed format: content must be mastered in Dolby Vision, and the display must have a Dolby Vision licence. Not all streaming services provide Dolby Vision streams even for content available in HDR; not all televisions support Dolby Vision even at higher price points.
HDR10+
HDR10+ is the royalty-free alternative to Dolby Vision — dynamic metadata without a licensing cost. The technical approach is similar: per-scene metadata that allows more precise tone mapping than static HDR10. Content availability is more limited than Dolby Vision, and display support is less universal.
HLG (Hybrid Log-Gamma)
HLG is the HDR format developed primarily for broadcast television by the BBC and NHK. Unlike the other formats, HLG does not contain absolute brightness metadata — it is designed to be compatible with both SDR and HDR displays without separate masters.
This makes HLG useful for live broadcast (where content cannot be mastered in post-production) and for services that need to serve a mixed audience of SDR and HDR viewers. Most HDR-capable televisions support HLG; it is the format most likely to appear in broadcast and catch-up TV content in the UK.
HLG is why your television may show an HDR indicator when you're watching a live football match. The BBC and several other UK broadcasters use it for live HDR output.
Tone mapping
Tone mapping is the process of adapting HDR content mastered at a brightness level your display cannot achieve to your display's actual capabilities. If content is mastered at 4000 nits and your display peaks at 600 nits, the display must decide how to compress those highlights into its available range.
Most televisions handle this automatically and reasonably well. The options in the settings menu — if they exist — typically allow you to choose between approaches: clipping highlights beyond the display's capability, compressing them uniformly, or using a roll-off curve that preserves some detail while managing the compression.
For most viewers the automatic or default tone mapping is adequate. Where it becomes worth adjusting is if you're seeing consistently clipped highlights in HDR content — bright windows appearing as featureless white, for example — in which case a slightly more aggressive compression curve may preserve more detail at the cost of some brightness.
What to check in your settings
The HDMI ports on most televisions need to be set to allow HDR input, which may not be the default. Look for HDMI Enhanced Mode, HDMI Signal Format, or similar settings in the input or display settings menu. An HDMI port not set to enhanced mode will not pass HDR signals from a connected device.
HDR format support on streaming apps depends on the app's capability, not just the TV. Some streaming apps require specific settings within the app itself to enable HDR output. If you're not seeing an HDR indicator when you expect to, checking the streaming app's settings and your HDMI port configuration is the useful first step — worth knowing before concluding the TV doesn't support the format.