720p 29.97 field dominance

[Kevin Wild]

Man, this stuff has given us a HUGE headache. I posted a while back on mixing all of these framerates, sizes, etc. Not much feedback…

The best way we’ve found is to bring it into After Effects, interpret footage to LOWER (SD) and size to SD from HD in AE…and then render out.

We have not found the Final Cut Pro “shift field” OR Kona LHe output or Nattress Plugin in FCP to be good enough at dealing with these frame rate and downconvert issues. We have had all sorts of problems mostly with graphics and text not downconverting well or having that field switch issue (HD=upper, SD=lower).

Hope this helps. The After Effects field convert works awesome.

Kevin

[Oliver Peters]

[Kevin Wild] “We have not found the Final Cut Pro “shift field” OR Kona LHe output or Nattress Plugin in FCP to be good enough at dealing with these frame rate and downconvert issues. We have had all sorts of problems mostly with graphics and text not downconverting well or having that field switch issue (HD=upper, SD=lower).”

Kevin,

The issues you are talking about above are Field Order, not Field Dominance. Apple improperly labels this in most of their FCS apps. In this case – Field Dominance – all 29.97 fps edits that start on Field 1 of an FCP 29.97 video stream are shifted to start on Field 2 in the SD downconversion – or to the even frames of a 59.94 fps progressive video stream.

Yes, you are right that AE does a better job of rendering and I have used that in the past. In this case, I’m trying to stick with the real-time benefits of the hardware. And yes, I haven’t received much feedback either on several different forums.

Cheers,
Oliver

Oliver Peters Post Production Services, LLC
Orlando, FL
http://www.oliverpeters.com

[Walter Biscardi]

[Oliver Peters] “One of my clients shoots P2 as 720p at native 29.97 fps”

There’s no such thing. 720 is 59.94, 30 or 24 unless you’re shooting with the Varicam where you can set some other frame rates.

[Oliver Peters] “It appears, however, that this output on both the HD feed and an SD downconversion to 525i is Field 2 dominant. Therefore, all edit points (normally Field 1 in FCP on other 29.97 formats) become split-field frames in the NTSC downconversion. Anyone know if this can be changed or reset in some way to force Field 1 Dominance? “

Lower Field first is correct for the NTSC Downconversion. If it’s upper field first you’ll have a reverse field interlacing issue.

Walter Biscardi, Jr.
Biscardi Creative Media
HD and SD Production for Broadcast and Independent Productions.

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[Jeremy Garchow]

[Oliver Peters] “And yes, I haven’t received much feedback either on several different forums. “

Hey Oliver. I have never seen this before and I want to test it out. Have you written or called AJA about this? This is not something that can be ‘fixed’ in the KOna Control Panel if it is indeed a problem.

If you’re working 720p30, you should be getting 30psf SD.

You’ve tried the obvious uninstall and reinstall the software and make sure you have the latest firmware on the card, right?

JEremy

[Oliver Peters]

[Jeremy Garchow] “Hey Oliver. I have never seen this before and I want to test it out. Have you written or called AJA about this? This is not something that can be ‘fixed’ in the KOna Control Panel if it is indeed a problem. “

Jeremy,

Since this isn’t my own system and I know AJA monitors this forum, I’ve started here among other places. I will check directly with AJA to see what they say. Thanks.

– Oliver

Oliver Peters Post Production Services, LLC
Orlando, FL
http://www.oliverpeters.com

[Jeremy Garchow]

[Oliver Peters] “I’ve started here among other places. I will check directly with AJA to see what they say. Thanks.”

No problem. It’s your best bet. PIcking up the phone and calling them will be the fastest as it’s very rare that AJA does technical support on this forum, all though they do listen 🙂

Have you done the software/firmware updates for the Kona? At least a driver uninstall and reinstall?

ALso, what deck are you going to? Have you tried a different deck or made sure the settings are proper on the deck?

[Oliver Peters]

[walter biscardi] “There’s no such thing. 720 is 59.94, 30 or 24 unless you’re shooting with the Varicam where you can set some other frame rates. “

Walter,

The P2 cameras can record in native and non-native frame rates. Check the record menus for both “P” and “PN” frame rates. So you can record 29.97fps or 23.98fps over 59.94fps, just like in VariCam. That would be “P”. However, you can also shoot native frame rates. This means the card is ONLY capturing 23.98 or 29.97 progressive frames. That would be a “PN” setting. When you drop this media into an FCP timeline, the timeline will set itself up with a timebase of 29.97 (if you set the camera to 720 29.97 PN) and “none” for its field setting. This is valid inside the software only. You are right that the format is 720p 59.94, which is why the Kona card doubles the frames. That’s not the issue. The problem is that it starts the frames on the even frame of a 60 frame stream or Field 2 of the downconverted, interlaced 525i signal.

[walter biscardi] “Lower Field first is correct for the NTSC Downconversion. If it’s upper field first you’ll have a reverse field interlacing issue. “

That’s not what I’m talking about. Apple is totally wrong in how they label this in the FCS apps. They are referring to Field ORDER as Field Dominance in their menu settings. So yes, Field ORDER is lower field first in NTSC, but Field Dominance of the edits can be either Field 1 or Field 2 in an interlaced signal. Most NLEs and VTRs are Field 1 dominant, but you will often find live video switcher feeds that are Field 2 dominant.

Thanks. I’ll check with AJA and try to post the info when I find out.

– Oliver

Oliver Peters Post Production Services, LLC
Orlando, FL
http://www.oliverpeters.com

[Oliver Peters]

[Jeremy Garchow] “Have you done the software/firmware updates for the Kona? At least a driver uninstall and reinstall? “

Not my system.

[Jeremy Garchow] “ALso, what deck are you going to? Have you tried a different deck or made sure the settings are proper on the deck?”

Tried both Panasonic 1200A and Sony Digibeta. The Panasonic 1200A is getting the 59.94 fps signal over HD-SDI and all edits from the 29.97p timeline occur on only even frames of the 59.94 stream. On the downconverted SD signal from either the 1200A or the Kona card directly, these same 29.97p edit points occur starting on Field 2 of a frame (Field Dominance).

– Oliver

Oliver Peters Post Production Services, LLC
Orlando, FL
http://www.oliverpeters.com

[Jeremy Garchow]

[Oliver Peters] “Not my system. “

I don’t understand that logic. Not your system which means…..What? You can’t touch it or trouble shoot it? If you’re driving a friends car and you get a flat, do you leave it at the curb while he comes and fixes it and you hop on the bus?

[Oliver Peters] “Tried both Panasonic 1200A and Sony Digibeta. “

That is very interesting. It’s been a good while since I have done a 30p project, but I certainly don’t remember this being a problem, although I can’t even remember if I checked it in SD.

Have you tried a firewire layoff just to test it?

[Oliver Peters]

[Jeremy Garchow] “I don’t understand that logic. Not your system which means…..What? You can’t touch it or trouble shoot it?”

I’m there as a freelance editor. They have staff post supervisor and pay Bob Z to do installs when it exceeds what they can do in-house. So no, I don’t proceed to install drivers, plug-ins or other software, unless I’m asked by the system owner. I think there’s a pretty long list of disasters here on the COW caused by editors arbitrarily installing software and accepting automatic updates 😉

Right now my effort extends to seeing whether or not there is even an actual problem first. After all, I’m being paid to edit content, not troubleshoot software, especially when there might not actually be a problem.

– Oliver

Oliver Peters Post Production Services, LLC
Orlando, FL
http://www.oliverpeters.com