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60i footage to 30p output?

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Spencer Honda
60i footage to 30p output?
on Aug 29, 2018 at 7:06:39 am

Shot some interviews that I'm sending over to a news station to use. I think they shoot 60i but my camera is sorta broken so that's the only option I have right now anyways. How do I work with this in Premiere? Do I set the sequence settings to 30p (29.97) or 60i? When the clips are in the timeline, do I set the field option to Always Deinterlace?

The only reason I ask is because I sent some clips a few years ago that I shot in 60i but it didn't look good when they used it. So I've shot 60p ever since and that seems to have been fine for them. But this time I'm stuck with 60i.


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Bouke Vahl
Re: 60i footage to 30p output?
on Aug 29, 2018 at 7:27:34 am

If they are a broadcaster they use 29.97 i
note, 60 i DOES NOT EXIST. It's 60 p, or 59.94 p.

Do NOT go to 30p. Go to 29.97 i.

Not sure about Premiere, but if you use AE, and set interpret footage correct, and put the footage in a 29.97 i comp, you should be fine. (It will time stretch, not sure about the sound. That should be (unnoticable) pitch shifted. Check for sync on long takes. Short (under a minute) should never be an issue.

Bouke
http://www.videotoolshed.com


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Sam Lee
Re: 60i footage to 30p output?
on Sep 6, 2018 at 6:19:39 pm

Is 60i is another way to express it as 59.94 fields (29.97 frames * 2 fields = 59.94 fields, established back in '53 by NTSC), which is essentially 29.97 interlaced frames for US broadcast?

60p and 60i are completely different. 60p is actually recording at 59.94 fps frequency when you look at the file's metadata. And the cam recording menu actually confirms it at 59.94p. My Varicam 35 doesn't have 60i. So 29.97i is the equivalent of 60i. Maximum frame rate is 30 fps for 60i. I originally thought I can get 60fps with 60i. But I was wrong when trying to set in on the Varicam 35/HS/LT cams. These 29.97i and 60i terms are confusing. I'd put 60f to denote fields instead of interlaced to minimize the confusion.

Putting 60p footage in a 29.97p timeline will result in ~2x slow-mo. These are completely 2 different frame rates and I'd be very careful not to have duplicate or dropped frames when confirming each footage to the sequence's constant frame rate (29.97

60i recorded clip after de-interlacing (using hi-quality method) is effectively equivalent to 29.97p. De-interlacing quality is subjective and can never be at the same quality as it was shot in its native progressive scan from the cam.

Most broadcasters are OK with interlaced video. Not sure why there's a need to "Always DeInterlace" if that footage is not mixed with progressive scan footage. If it's mixed with progressive scan, then deinterlace it to match.


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Bouke Vahl
Re: 60i footage to 30p output?
on Sep 7, 2018 at 4:06:21 am

[Sam Lee] "Is 60i is another way to express it as 59.94 fields (29.97 frames * 2 fields = 59.94 fields, established back in '53 by NTSC), which is essentially 29.97 interlaced frames for US broadcast?"

Yes, and as you agree, it is a very bad / stupid way of describing normal speed interlaced.

[Sam Lee] " 60p is actually recording at 59.94 fps frequency"

Not always. 60p (as well as 30p) actually exists. (Mostly in consumer / action cams.)
So, sometimes it's 60 or 30, sometimes it's 59.94/29.97.
(And yes, that sucks too if it's not always the correct number.)

[Sam Lee] "60i recorded clip after de-interlacing (using hi-quality method) is effectively equivalent to 29.97p."

I though we just established that 60i DOES NOT exist?
For the 0.1 % speed difference, a speed change (if needed) is very well acceptable, just pitch shift the sound as well to stay sync.

[Sam Lee] "Most broadcasters are OK with interlaced video."
I would say ALL broadcasters, except Netflix and other online platforms.


[Sam Lee] " If it's mixed with progressive scan, then deinterlace it to match."

Why? If the mix looks good, it is good. (Especially motion graphics can be interlaced in a progressive sequence.)

Bouke
http://www.videotoolshed.com


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Sam Lee
Re: 60i footage to 30p output?
on Sep 7, 2018 at 1:44:30 pm
Last Edited By Sam Lee on Sep 9, 2018 at 2:06:34 pm

Ah. Thanks for bringing this up. Looking at the metadata fields for Go Pro, DJI Osmo, I see that 60p is at 60 fps. The Varicam 35/HS series records it at 59.94 fps. Not a big concern if the footage is used as visual cutaways with no audio.

Amazon Prime Video accepts native interlaced scan masters. This saves a lot of time and expenses by having to deinterlace it for delivery. But they'll de-interlace the video when ingested and viewed on the subscriber's end.



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