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FCP Field Issues

 

I have been editing my reel with FCP 4 and I have found the output seems to have reversed field order. The source material is DV PAL and I have checked the source "data" on another machine and it was fine.

I have changed the field order to "lower field" in the sequence setting and in the individual clips properties the field order is "lower field" but I am still screwed. I have run out of ideas. Anyone been here?

Many Thanks
Tom Gleeson DOP (but crap editor)
www.cinematography.net


That is very interesting. I have also had FCP field order issues, but when transferring After Effects output from my lap top where they are fine in FCP, to a desktop for inclusion in a piece where they suddenly become jerky as hell.

We've been through all the settings we can find in AE and FCP and the problem will not go away, to the point where we transfer stuff the other way round and play out from my G4 powerbook.

I'd be interested as well as Tom to hear if anyone has solved any field order related troubles.

Chris 'out of order' Merry


Tom

You need to give us more details on where and on what you're seeing these issues. Monitor? Burnt DVD? I presume you're talking about reversed field order right?

What do you mean by "I have checked the source "data" on another machine and it was fine."?

Martin Baker


Chris Merry wrote :

>Tom, what are you playing back from, DV-out?

We had this issue with material originally captured via firewire, and when it came out via a DeckLink Extreme, it was all jerky. A re-render of the timeline to Blackmagic 8-bit fixed this.

Cheers

Martin Heffels

Filmmaker/DP/editor/filmschool Techie
Sydney, Australia


>You need to give us more details on where and on what you're seeing >these issues. Monitor? Burnt DVD? I presume you're talking about >reversed field order right?

Martin,

Sorry about the slow pace of the reply but I have been shooting and also perusing some ideas to solve this although they have all ran into a brick wall. Yes I assume the problem is "reversed field order" I have set lower field dominance in both the sequence and clip settings (PAL DV Project). Strangely only affects some clips and not others.

One clip even changes half way from fine to jerky. On the TV monitor playing the troubled clips the movement looks only a little strange but if I freeze frame on movement it judders. When I burn a DVD (FCP-compressor) movement on these clips look weird with jagged tearing on the movement.

I can deinterlace the clips and solve the problem but a bit drastic. Do you need any other information? Can I reverse the fields back?

Many Thanks
Tom Gleeson


Tom Gleeson wrote:

>Strangely only affects some clips and not others. One clip even >changes half way from fine to jerky.

Are you doing some speed changes in these clips?

>On the TV monitor playing the troubled clips the movement looks only a >little strange but if I freeze frame on movement it judders.

I noticed that. Somewhere in the video-filters, you'll find a anti-flicker filter, which you can apply to the flickering clip (it has 5 settings).

>I can deinterlace the clips and solve the problem but a bit drastic. Do >you need any other information? Can I reverse the fields back?

Given that you set your project to lower-field dominance, reversing them should not be the thing to do. But again in the video-filters, there should be a filter to reverse the field-dominance.

Cheers

Martin Heffels

Filmmaker/DP/editor/filmschool Techie
Sydney, Australia


Hi Tom,

The problem with FCP and field order is that in PAL SDI and analogue land, our field dominance is UPPER. While in PAL 'DV' (DV25, DV50, DV100 etc) land, our field dominance is LOWER. DeckLink cards (I've got both a Pro and an SP) perform on the fly conversion from DV to 8bit UC and flip the field order. If you've captured via SDI and converted to DV, you'll get similar problems.

Which doesn't solve your problem(s). It could quite simply be an issue with that particular image...or with your settings (Compressor on 'auto' field detect). Flicker filter in FCP works well, or you can use FieldsKit or, if you're willing to wait a LONG time (and pay), get someone to run it through Magic Bullet.

If you like, forward me a still from your reel and I'll look at it and determine if its any particular issue with that shot.

All good reasons to shoot with the SDX-900

Stu 'Been using FCP since v1 when it wasn't even qualified for PAL' Willis.
Jack of all trades ... Master of none.
Sydney, Australia.



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