24Hz frame rate on Apple TV
The update to 11.3 brings an improvement in frame rate options. The ATV will configure its output and your set to the regional standard - 60Hz in the USA and 50Hz in the UK. This works well for TV programmes, but if you watch films there is a potential problem.
The film files are actually in 24Hz, the standard for cinema films. When you run these in 60Hz (60 fields) the ATV performs a conversion to alternate frames at 2 and 3 fields, which converts 24 frames to 60 Hz with slight jerkiness. However if you are in the UK and are set to 50Hz the conversion is much less smooth and results in two jerks per second which is much more distracting (each frame=2 fields except numbers 12 and 24 in each second). (UK broadcast TV runs films at 25 frames per second to get round this).
If you are in the UK you are better off setting it to 60Hz for films; however if you have a set capable of handling 24Hz (many modern sets do to cope with Blu-rays of films) you can now set the ATV to output 24 Hz which produces the correct result. If you go to Settings>Displays and Audio and select the Display Resolution there is a 'more options' option on the menu: click that and one of the options is 1080p 24Hz; this is what you want if you mostly watch films.
If you are varying between watching TV and films you may be better off allowing the ATV to set itself to the regional standard and then enabling “Settings> Video and Audio > Match Content > Match Frame Rate > On” which will switch the frame rate to 24 Hz when you start a film.
