We have a client who has supplied some NTSC material which has been - as far as I can tell - been shot at 29.97. We are in PAL land so not so used to handling NTSC material
This is going on a DVD (staying at NTSC). They have asked for it to be deinterlaced. Not sure why.
I have a feeling they are muddling up deinterlacing to make Progressive and Reverse/Inverse Telecine when you take 29.97 FILM material shot at 24fps and Inverse Telecine it back to 23.98 and encode that to make NTSC progressive which when played back on a DVD player is played back as 29.97 with 3:2 pulldown except if the player can handle progressive material (as most modern players/tvs can)
However if the material has been shot at 29.97 surely I can't/shouldn't apply inverse telecine and there is NO advantage in just deinterlacing.
You're not missing a thing. You're also right about film-tape transfers: the pulldown must be removed to create 23.976 (aka 23.98) files prior to editing.
I would ask the client WHY they specify deinterlaced footage. There may be a silly reason for it, which you can easily explain away. If you're used to dealing with interlaced PAL, you're also used to dealing with interlacing throughout the project. It's no different in NTSC.
All SD video contains two fields, even SD video shot in progressive scan. PAL or NTSC makes no difference.
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