23.98 vs 24 -out to 1080i

[stu aull]

Hey folks - new to HD (jeez)
before I tread to far down the wrong path, some clarification?

Right now, based on research on RedUser, I have set up to record at 23.98 as the time base for field acquisition. Frankly most of my commercial output requirements from broadcasters seems (in-State) to be finalled as 1080_i_.

Any advantage or big disadvantage of sticking with 23.98 v 24? I know Progressive is correct, just trying to grasp nuance of 23.98/24/29.97/ yadda-yadda and what conversion or mixing-of-bases issues etc. I am getting into, esp down the road.

Hope I have provided enough info here, happy to provide more.

Stu Aull
SX 199
Alaska

[Marc Wielage]

Almost all HD deliverables are done at 23.98fps and 23.98-frame timecode. I would check with your distributor and make sure you know their requirements -- in writing -- to the letter.

The conversion from an edited HD master at 23.98 to 1080i is very simple and straightforward, either files or videotape (or both). 23.98 can still be progressive.

[David Mullen ASC]

In North America, 1080i runs at 59.94 Hz, so you would be converting 23.98P to 59.94i. I believe if you tried converting 24P, it would just run it at 23.976 fps anyway and add the 3:2 pulldown to get to 59.94 Hz. At that point, the main issue is audio sync if you had shot 24P but where running it at 23.98P to convert to 59.94i. So just shoot at 23.98P.

[stu aull]

Thanks Gents - this is what I understood was correct - appreciate the confirmation!

regards
Stu Aull
Alaska