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Problems converting 23.98 program to 29.97

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Guy Mellitz
Problems converting 23.98 program to 29.97
on Jul 30, 2019 at 6:08:57 pm

I have a program that was cut in 23.98 (1080p) and am being asked to deliver a 29.97 (1080p, *not i*) master. My current workflow is to mixdown the 23.98 sequence, open that bin in a 1080i/59.94 project and lay it into a new sequence, then export it at 1080p/29.97.

The problem is, I've tried virtually every combination of Motion Effect setting (frame interpolation, output, etc.), and even tried several different export settings, but I either get duplicated frames (leading to a 'stutter') or I get blended frames on cuts. I've even tried using Adobe's Media Encoder in various ways to try and get things to look right, but nothing seems to work.

Does anyone have any suggestions? I'm really at a loss.


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Shane Ross
Re: Problems converting 23.98 program to 29.97
on Jul 30, 2019 at 6:16:04 pm

[Guy Mellitz] "My current workflow is to mixdown the 23.98 sequence, open that bin in a 1080i/59.94 project and lay it into a new sequence, then export it at 1080p/29.97."

What? NO nononononononono. That's not what you do at all. That's what you do when you want to PROPERLY add pulldown to get 23.98 to 29.97 interlaced. But 29.97p? That's almost the worst way to do it.

There is really NO good way to get 24p to 30p. No matter what, you'll get repeat frames. You can try Fluid Motion, or even After Effects, but if there's fast movement, then you get the jelly effect either on the moving object, or in an "aura" surrounding the object.

Even higher end converters might jelly on motion, but some do a decent conversion (Talking about the Alchemist here).

So, if you shot and edited 23.98, and are asked to deliver a 30p master (if they wanted 30p, then it really needs to be shot 30p)...they either need to live with the slight stutter look of 6 additional frames, or you need to take the master to a post facility with Alchemist, have them run a test conversion and see if the client is cool with that.

24p to 30p isn't a smooth conversion.

Shane
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Read my blog, Little Frog in High Def


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Guy Mellitz
Re: Problems converting 23.98 program to 29.97
on Jul 30, 2019 at 6:32:22 pm

Yeah, the thing is, I even checked to confirm that they wanted 29.97p, and was told "yes", but that "the final export will be interlace but we make that one" which seems really dumb to me.

I definitely can't bring it to an Alchemist, and Fluid Motion/Optical Flow is really not going to work (because of the morphing effect you mentioned).

I tried exporting it as interlaced, which seems to be ok, though the frame blending seems a little bit jittery (yet not as bad as repeated frames. I may have to just do that.


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Shane Ross
Re: Problems converting 23.98 program to 29.97
on Jul 30, 2019 at 11:05:53 pm

The main reason some clients...and networks now....want 30p is so they can post the video online, as the web and interlacing don't mix. The fact that they say they will interlace on their end...TO ME...reads as they will broadcast this on air at some point...but also want a progressive version for the web. Which makes me wonder...why are they insisting on a 30p master? They can put the 23.98 one on the web and not have it skip and it'll play fine. Why do they want 30p? Why not accept the 23.98p, add pulldown to create a 1080i60 master for air, but put the 23.98 online?

That's what I'd be asking the client. Explain the issues of 24p to 30p conversion...and that interlacing that will make it look worse than 24p to 60i conversion would.

Shane
Little Frog Post
Read my blog, Little Frog in High Def


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Guy Mellitz
Re: Problems converting 23.98 program to 29.97
on Jul 31, 2019 at 12:43:36 am

These are all excellent questions I've been wrestling with all day. Unfortunately, the contact I have is, I believe, an AE who is probably doesn't really know, or is unauthorized to stray from what he's been told to do. I would love to give them both 24p and 30i versions, but I'm not sure that I'm allowed to.

You're correct that this ultimately will be broadcast, hence the 'i'. Beyond that, he says "We sometimes deliver other versions that are progressive, it’s just the broadcast master than needs interlace. Starting with interlace makes it tougher to make the progressive masters."

After trying virtually every combination of frame interpolation and export setting imaginable, I'm actually back to square 1 which, despite your reaction, seems to in fact look the best. However, there is of course visible 'banding' (in addition to the blending at many of the cuts). Basically, it gives me 3 normal frames, then 2 blended ones, 3 normal, 2 blended, etc. If a cut falls on one of those 2, they're blended.

I think what I have to do is send them what I have, point out the banding/blending issue and see if it's possible to deliver the 2 separate versions.

In answer to Jeff's question: If I try to export the 24 directly to 30, I get duplicated frames, so there's a stutter. If I bring it in to a 60p project, I no longer have the banding issue, but basically every frame is blended, so it's as if there's a 1 frame dissolve on every frame. Can't have that.

Incidentally, thank you both for your help. I appreciate it.

Guy


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Shane Ross
Re: Problems converting 23.98 program to 29.97
on Jul 31, 2019 at 12:59:48 am

[Guy Mellitz] "Unfortunately, the contact I have is, I believe, an AE who is probably doesn't really know, or is unauthorized to stray from what he's been told to do."

Then try to get higher on the tech chain there. Contact someone in charge, and present the issue. Present the idea of delivering 23.98 masters, that they can then interlace, or you can also provide the 60i masters. But yeah, you need to reach out to their head tech guys...having a minion insist on what you deliver is not a good call.

[Guy Mellitz] "Beyond that, he says "We sometimes deliver other versions that are progressive, it’s just the broadcast master than needs interlace. Starting with interlace makes it tougher to make the progressive masters.""

Good, then deliver a progressive master, and an interlaced master. But yeah, let someone know that your footage is 23.98, and your master is 23.98, so delivering 30p for web delivery makes no sense. but 60i for broadcast does, and is totally doable.

Shane
Little Frog Post
Read my blog, Little Frog in High Def


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Jeff Pulera
Re: Problems converting 23.98 program to 29.97
on Jul 30, 2019 at 8:30:52 pm

In the immortal words of Shane Ross...." nononononononono."

I don't get why you would add the step of going to 1080i then back to 1080p, what in the world for? Just go straight to the 30p (29.97p actually) the client is asking for.

Thanks

Jeff


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