Research Into Audio Delay In Film, and What FPS To Use

Surprisingly there is very little information online regarding the audio delay, and most of the internet is flooded with information regarding how to fix audio synchronisation errors! I did find that you should use a delay of a mili second or less if you are going to create the diegetic sound in a studio, or if you are synchronising audio, the is to replicate the audio delay that you naturally get.

Frame rate	Media	Description
23.98 (23.976) fps	Film; high definition video with NTSC compatibility; NTSC	This is 24 fps slowed down by 99.9% (1000/1001) to easily transfer film to NTSC video. Many high definition video formats (and some SD formats) can record at this speed, and it is usually preferred over true 24 fps because of NTSC compatibility.

I found the above graph on Apple's website, and also some other reputable sites. It states that most people believe that film is is shot on 24 frames per second, it is actually 23.98 FPS. 

The reason for most of the media using this standard is because when audio was introduced to film, creators wanted the media to appear more life like, and less staggered than the previous standard of 16 FPS. 

A frame rate of 60FPS was used in the Hobbit, but received much criticism because of its video game like appearance.