I’ve been on an internship at a post-production house called Studio Post for a little while now. And in the past two and a half weeks I have learned lots. Particularly when it comes to framerates. Now this has brought something to my attention.
Let’s say you’re shooting a documentary. Being a documentary you’re going to get footage from everywhere. Archival film, newly shot interviews, what have you. Now in an example with the archival film (23.98) you would convert it to 29.97i with pulldown.
(image of 3-2 pulldown from avchduster.com)
Then you’ll proceed to edit with everything at 29.97 and finally mastering in 29.97. Doing this prevents you from be able to do the; following.
You can’t make a progressive scan Blu-ray, because the format doesn’t support 29.97p, only 29.97i
You can’t convert the master to PAL without introducing serious motion artifacts, even on the best conversion hardware.
You would’ve “baked in” the 3:2 pulldown pattern of the archival footage and that cannot be removed on playback, leaving repeated fields, or ghost images. (This gets even worse when you convert the frame rate to 25 for PAL).
Or you shoot all your new stuff at 23.98 (and obviously don’t convert the film footage). Edit and master in 23.98 and by doing this it lets you do the following.
Deliver an NTSC DVD that will play progressive.
Deliver a progressive scan PAL master to non-NTSC countries by speeding up the 23.98 master to 25fps - with this method you have *no* motion artifacts, because you’re doing a 1:1 frame mapping, just playing it faster, effectively.
Create a Blu-ray with a progressive-scan frame rate (23.98) that will play worldwide.
Create 29.97i masters for broadcast, simply by adding 3-2 pulldown when the master is dubbing to tape.
Now there is a lot of resistance to working in 23.98. Heck I’m guilty myself opting not to shoot in 23.98 on the last documentary I did. But now with this knowledge I am not sure why working in 23.98 is not oped for. It’s easy to convert to PAL, 24 and 29.97. I guess it’s just an old rivalry between film and TV in North America. Alternatively you could just move to PAL land and your life will be so much easier.
