TechReport (UK)

HDR (High Dynamic Range)

If UHD / 4K has been the major new TV feature of the last few years, then HDR is certainly the next.

The term ‘High Dynamic Range’ refers to the ability of a TV to display a more ‘dynamic’ (clever use of words here!) picture by extending both the range of colours and range of brightness levels (from the darkest black areas to the brightest white areas) within the picture that the TV can accommodate.

Regular (non HDR) TV’s have an ‘8 bit colour depth’ (Red x 256 levels, Green x 256 levels, Blue x 256 levels) offering 16 million colours which can cover about 35% of the range of colours that the human eye can distinguish. HDR TV’s have a 10 bit colour depth and so can offer the more than 1 billion possible colours, covering about 50% of the human eye’s range (as you can see, the range covered by the human eye is not linear).

The improvement in the contrast range of the TV the (blackest black to the whitest white) should present an even greater improvement in the picture – the viewer should be able to resolve much more detail in the very dark areas of the picture and be equally impressed by representation of very bright short-term events (such as explosions) on the screen:

Arguably, the improvements offered by the use of HDR technology represent a much more obvious enhancement to the viewing experience than did UHD / 4K before it.

    As the term HDR was initially applied to cover many different ranges of colour and brightness, the industry has since coined a new standard (to cover TV and Blu Ray hardware, as well as the production of compatible source material) – ‘Ultra HD Premium’.

Rather than go into detail, suffice it to say that this effectively means an UHD / 4K TV with the ability to display a sufficiently wide range of colours, a sufficiently low ‘black level’ and a sufficiently high ‘peak white level’ simultaneously (i.e. within the same picture) to give a true HDR viewing experience.

Most of the 2016 range of premium models from the major manufacturers will meet this standard (and will invariably display the logo in their marketing blurb).

Whilst Ultra HD Premium Blu Ray Players (and suitably mastered Blu Ray disks) are currently rare and expensive, Netflix (and others) have already begun to stream HDR content that is compatible with this standard and more will inevitably become available in the very near future.

Note: Some HDR TVs also incorporate a facility to ‘enhance’ non HDR source material by ‘upscaling’ standard content to give it the appearance of having a higher dynamic range. The Samsung version of this is known as HDR+:

HDR+ Off:

HDR+ On:

Next: ’Smart’ (‘Connected’) TV

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