Play a film or TV show and the picture you see is actually made up of a multitude of still pictures played very quickly, one after another, to fool your brain into thinking you’re seeing motion.
Traditionally, films have 24 of these images – called frames – every second. This number was originally chosen not only because it was considered high enough to give the resultant image a smooth impression of motion, but also to allow a decent quality of sound (sound was embedded into the film at this point).
Television programmes work to different standards. In the PAL system (used in Europe and parts of Asia) the rate is 25 frames per second while NTSC (the North American alternative) sets the frame rate at 30. These aren’t arbitrary numbers. They are tied into the mains power frequencies in each of those regions - that’s 50Hz for PAL territories and 60Hz for NTSC.
While the term ‘High Frame Rate’ is routinely bandied around there is, in fact, no fixed standard. In effect the term refers to any frame rate higher than is conventionally used - so anything better than the current 24-30 fps.
What can I watch in HFR?
Arguably the most high-profile HFR films to date have been Peter Jackson’s The Hobbit trilogy - they were recorded at 48fps. Having more frames per second inherently improves the smoothness of motion, and gives a higher degree of resolution and clarity. Watch any of The Hobbit films and each of these advantages are clear - but not everyone liked what they saw.
Why? The extra smoothness and resolution makes the films look more lifelike, but also very different from the norm. We’re so used to seeing the grain and relatively low resolution of traditional film, anything so obviously better can just look odd. The extra clarity puts more of a spotlight on set quality, special effects and make-up - so any shortcomings in these areas are now spotted more easily.
Ang Lee went even further than Jackson with Billy Lynn’s Long Halftime Walk. This was recorded at a heady 120fps, and met with equally mixed reactions. The very high level of resolution and smoother motion are obvious, but many viewers remained unsettled.
Elsewhere, many of the big name game franchises such as FIFA, Call of Duty and Forza have incorporated 60fps in some editions. YouTube has a number of clips too, but little to hold our interest for long.
It’s fair to say there’s a scarcity of HFR material, but that can change quickly. James Cameron's upcoming Avatar sequels are said to feature the technology, and that could well kick start something of a revolution, much as the original did for 3D.
Will I need a new TV?
HFR is already sneaking into the spec lists of a number of TVs. LG has been particularly keen on the tech, having included it on its 2018 and 2019 OLED models. That said, there's very little that you can watch at home in HFR right now and by the time there is it will be supported by most new TVs thanks to its inclusion in the HDMI 2.1 spec - although those TVs will also need a processor powerful enough to work with the high frame rate signal it's receiving.
In short, it's not really worth getting too caught up with HFR right now, but the situation should be much clearer as we move into 2020.