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Hi, all
I posted about this situation earlier this week, and got some good feedback. But, now I've encountered a novel problem, and I think it may just be unsolvable, but I thought I would see if any of the wizards here have a solution.
I'm having that problem that usually results from a conflict in field dominance between a clip and a sequence. When something moves in the frame, the interlaced fields fall apart, and instead of nice motion blur, I have interlacing.
Here's what's weird. I've got two angles on a bunch of people speaking at a podium. Angle 1 shows curtains behind him, and Angle 2 has just darkness, Charlie Rose style. I am cutting between these two angles. They were both shot on the same camera, and they show all the same settings in the project (Compressor, Frame Size, etc.). But, whereas Angle 2 has nice motion blur when somebody gesticulates, Angle 1 has mis-interlaced fields.
The project was captured to AJA Aki Pro recorders, at 720x486, 29.97 fps, Apple ProRes 422, NTSC-CCIR 601, with lower field dominance, naturally. When I place this in a sequence that matches those settings, of course I have no problems.
But, I have to deliver in XDCAM HD422 720p 59.94 fps. So, I created a sequence with these settings, and dropped my show in, so that I could balance the acts in the proper frame rate, and create Motion graphics in 720p, which looks a lot better than in SD. I can only have no field dominance in this format. My pixels are square.
Now, I have a problem with just that one camera. Which, unfortunately, is an essential angle that I use throughout the show.
I feel like I need to move to a sequence in the delivery frame rate in order to balance the acts with frame accuracy for broadcast. Is there a way around this? Should I change my workflow?
Thanks very much!
But, I have to deliver in XDCAM HD422 720p 59.94 fps. So, I created a sequence with these settings, and dropped my show in, so that I could balance the acts in the proper frame rate, and create Motion graphics in 720p, which looks a lot better than in SD. I can only have no field dominance in this format. My pixels are square.
You can't just drop an SD clip into an HD timeline and expect FCP to give you a pretty picture. The footage needs to be converted properly. We use the AJA Kona boards for this all the time as they give us full broadcast quality SD to HD, HD to SD and HD Cross Conversion in realtime.
So in your case I would edit and finish the entire show in SD, then run it through the Kona board at the end to upconvert it to 720p.
If you don't have a Kona board, then you can do the conversion in Compressor and then bring your HD clips into FCP for editing. Or do the same idea as above, finish the entire show in SD and then convert everything, though I can tell you your graphics will not hold up as well with the conversion through Compressor.
And I'm curious, you really need to deliver an XDCAM 720p file? Honestly have never heard of that as XDCAM is almost always 1080. I know it supports 720, but I've only heard of folks using that format with 1080. That's interesting.
Walter Biscardi, Jr.
Biscardi Creative Media
biscardicreative.com
Yes, I agree that it is a strange delivery format. I have been trying, from before production, to try to get the producers to contact the network and ask if there is any flexibility on that. They haven't followed through. All I can say is that they gave us very specific file delivery specs, and those were them.
I don't have a Kona card in this system-- it's not something the producers felt inclined to rent, and I don't own one on my home system. I'm not calling this the most high-end gig I've worked on. But, then, it's January. I'm always glad to have a gig in January.
I fully appreciate the hazards of dropping SD into HD. Not generally the way I do things. We were taken by surprise by the SD thing at the event-- they had told us they captured in 720p. And, given that we have had a week to turn around the show, I haven't had a lot of time to experiment.
In fact, they could have done the 720p conversion at the event while recording to the AJA Aki Pro deck, which is why they believed they could deliver in 720p even though they were shooting 525i. But, I was confronted with a bunch of different formats (we had HVX's shooting red carpet and backstage material) and in the moment I felt like capturing at the native format of the camera was the wisest decision. They also told me that the Aki Pros could convert to 720p during capture to FCP (which was, in retrospect, ridiculous considering how the Aki Pros capture).
I will see if I have time to do a Compressor conversion of just the shots from that one camera.
Again, the weird thing here is that only one of the two cameras filming the podium has this problem.
Thanks much!
I realize that I've been calling the Aja Ki Pro the Aja Aki Pro. Correction.
Compressor does seem to fix the problem.
If I ship a whole sequence to Compressor, will it go to my source files on the graphics, and convert them from their HD format? Or, will it use the render files that are in the sequence?
Quote
I realize that I've been calling the Aja Ki Pro the Aja Aki Pro.
actually kind of like that name. I'd buy it
Michael Horton
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To add to the weirdness: The problematic camera recorded two clips. On the first clip, the problem does not exist. On the second clip, it does. So, it's not even that camera. It's that particular clip from that camera.
Is the brightness or luma out of spec on that particular clip?
I mean chroma or luma. Early here.
Hm, that's an interesting question. They are standing in front of a very saturated curtain (white curtain, illuminated by stage gels). But, my colors don't seem off the chart in the vectorscope. My blacks are a little deep, touching down at -10 IRE. Do you think this would affect the interlacing?
I have seen bright reds and yellows go pretty wonky - what happens if you reduce the brightness and chroma? Still a problem? I could be way off track here, but red edges do get nasty.
Hm. It is bright yellow. I asked them not to use red, because I know that causes trouble in SD broadcasts. I've never seen this kind of trouble. But, I'll try correcting it, and see if that makes the problem go away. Thanks!
This is a tough issue to troubleshoot without seeing the image. Can you export a few frames?
www.strypesinpost.com
Sure, I can export a few frames.
Here's an interesting issue: I put the broadcast legalizer on the image, to see if just constraining the luma and chroma would help. When I have "Show Excess Luma" on in the Canvas, the problem goes away. When I turn it back off, the problem comes back.
I'l export a few frames and post them. If I can figure out how.
Thanks!
It's pretty hard to see in that video. If you look at his hand waving around, you can pick it out, but maybe only if you know what you are looking for.
Yeah I'm not seeing anything horrific - I thought it was really jagged. It just looks like webwork. Which part is specifically bothering you?
Of course, we're looking at computer screens..
It really doesn't come across on YouTube. But, no, it is not horrific. It looks like what happens when there's a conflict between a clip's interlacing setting, and the interlacing setting of a sequence. It's clearly a mistake, and I have no idea if the network's QC will pick up on it. Regardless, it's something that ought to be fixable. But, to the casual observer, it may just look like ugly video, not f'ed up video.
I'm still curious as to why turning on FCP's zebra bars makes it go away.
Export a few frames as a self contained QuickTime movie and upload to yousendit.com
www.strypesinpost.com
I just realized that adding a de-interlace filter fixes the problem.
Just looked at your QT movie. Yes, you need to do the conversion properly, as Walter Biscardi mentioned. I would up convert the footage through Compressor (or send it through the AJA Kona card or a Teranex). Deinterlacing will only soften the image further as it removes the other field. It will get rid of the lines, but the picture will look MUCH better if you convert it properly.
www.strypesinpost.com
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