Quick question 24 or 23.976

[Chris Longley]

Doing quite a bit of HD CGI at 1920 x 1080, am rendering at 24fps.

A lot of the templates have 23.976 as an option.

Should I be using this instead?

The 24fps stuff plays back fine on the computer hooked up to plasma TV

My understanding is that 23.976 only exists as it's easily converted to NTSC on-the-fly?

I'm worried though that maybe I should be rendering using 23.976 if in future I want to author some of this stuff to Blu-Ray, or print it to tape on an HD camcorder?

[Alan Roberts]

In most instances I've come across, the term "24p" actually means 23.98 (actually 24/1.001), and it's there so that there's a simple (but nasty) relationship between it and the 59.94 field rate of NTSC. True 24p has relevance only if your delivery is 24Hz, i.e. to real film for cinema.

But, the newer big displays will treat both 24 and 23.98 the same, and do a nasty 2:3 pulldown job to show it at 60 or 59.94Hz. Quite why this is though to be a good idea is beyond me, because thne vast majority of the plasmas out there will quite happily up-convert to 100Hz from 50i, so they should be able quite easily to up-convert 24p or 23.98p to 96Hz or 96/1.001Hz. It's dramatically easier to do this in a plasma than in any other type of display, a trick that;s now being mimicked in some Philips crt tv sets.

In production terms, the only real difference between 24p and 23.98p is in the time code, 24p has continuous code whereas 23.98 has the discontinuous timecode of drop-frame, so you can get into some nightmare situations in the edit unless you know what you're doing. If your footage is mute, there's no problem, it's only when sound's involved tnhat it gets tedious.

Hope that helps.