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Aloha
I am working in a 1080 P /30 FPS prores time line with 30 FPS files that were rendered out at 30P fps in AE then imported into FCP version 7. Am I correct to assume that these clips should be automatically de interlaced since they were created in Progressive not Interlaced? The issue I am having is that some of the clips appear to be interlaced. Would de-interlace fix this or is it something else? This seems to happen when I speed the clip up.
Thanks
Sean
Sean, if you have progressive clips that "appear to be interlaced" this means the clips were miscreated. Deinterlacing can't be applied to them now.
Trace the steps.
What did the camera make, 30p, 60i or what?
What was done to the camera footage in AE?
Are you sure AE output 30p files? One way to check is to start a fresh FCP sequence and paste an AE file into it. If FCP asks to change sequence settings say: Yes. Then see what settings FCP chose for it.
What do you mean by "appear to be interlaced"? FCP is good at hiding interlacing in its canvas. Did you set the canvas at 100% and see combs, or what?
What do you mean by "speed the clip up"?
It might help both your observing and diagnostic powers to do more book study of what video interlacing is. It's a confusing subject, partly because of conflicting terminologies. You shouldn't have written '30P fps' and you probably meant non-interlaced where you wrote 'de interlaced'. This sounds fussy, but by misunderstanding one instruction and checking one wrong box you can make a royal mess of a clip.
Dennis Couzin
Berlin, Germany
Ok thanks for the help. Yes you are correct that I mislabel de-interlaced with non interlaced.
Ok so I checked the timeline settings and it was set to Lower Even field dominance. I changed that to none .
I noticed that I can not change the project to 30 fps. It is at 29.97 for an editing timebase. When I try and change to 30 it tells me Frame Rate change Ignored - use the editing timebase to specify the frame rate preset. How do I change to 30? I am using Prores 422
Also when I do i final render so I clear out all the renders - It seems I have corrupted clips - they exported fine before and now they give me errors
Thanks again
Sean
Sean:
If you place a 30p clip onto a 60i timeline and then render, FCP does not make good 60i video from it. It does make 60 fields from 30 frames but those 60 fields show the original 30 moments of time, not 60 moments of time as true 60i video does. Using the FCP player, the 30p clip rendered on a 60i timeline can't "appear to be interlaced" as you described in your first post. So I don't think your mistake was simply a wrong sequence setting in FCP.
On the other hand if you place a 60i clip onto a 60i timeline the FCP player will show the interlacing as combing (when the canvas is set to 100%). I think this describes your case. I think some or all of your AE files are 60i (59.94i to be exact).
If you place a 60i clip onto a 30p timeline and then render, FCP does not make good 30p video from it. It does make 30 frames in place of 60 fields, but those 30 frames are constructed from just 30 of the fields, the others are discarded. This is a serious loss of spatial as well as temporal information. I think this is what you're doing now.
Dennis Couzin
Berlin, Germany
There is however the speed ramps and slow mos. With those, FCP will take the image, blend them and re-sample that into either interlaced fields or progressive frames depending on the sequence settings.
www.strypesinpost.com
strypes: good idea but I don't see it for Sean's case.
If the imported clip is genuine 30p (with no interlace artifacts) and the sequence setting is 60i then speed changes (whether >100% or <100%; whether Frame Blending is turned on or off; whether Motion Filtering Quality is set Best, Normal or Fastest) don't introduce any interlace artifacts. They logically could, but in FCP they don't. That's why I think Sean's import wasn't genuine 30p.
(I'm distinguishing a "genuine 30p" clip from, e.g., a 30p clip whose frames are sums of consecutive fields of a 60i clip, something that can easily happen due to the way digital video is stored.)
Dennis Couzin
Berlin, Germany
No. Try it. Take a progressive clip like a time-lapse and do a 500% speed change. Render and export it. Take a look at it.
www.strypesinpost.com
strypes, of course I tried it, in all the variations listed, without seeing that. What are we doing differently? Details off line.
Dennis Couzin
Berlin, Germany
Is your FCP sequence/clip set to upper field dominant? Coz I see that a lot. It's not exactly an interlaced artifact per se like inverted fields, but the clips becomes interlaced after you render it.
www.strypesinpost.com
strypes: yes, I tested to see what happens when a progressive clip is dropped into an (upper field dominant) interlaced timeline and then editing actions performed (such as speed changes) in FCP. After rendering, the exported clip is interlaced, but there are no interlacing artifacts -- no way to see with one's eyes (within FCP) that it is interlaced. Remember, we're trying to reconstruct what the original poster saw.
This whole exercise is based on FCP7's limitations concerning interlaced video. I wonder if FCPX handles interlacing better, or even worse!
> After rendering, the exported clip is interlaced, but there are no interlacing
>artifacts -- no way to see with one's eyes (within FCP) that it is interlaced.
Set canvas to 100%. You should also be able to see that on the broadcast monitor.
www.strypesinpost.com
strypes: if an interlaced clip has been created from a progressive clip by means of the sequence settings, so the 1st field gets the odd lines from frame 1, the 2nd field gets the even lines from frame 1, the 3rd field gets the odd lines from frame 2, etc. then there is no way to see that it is interlaced. The canvas at 100% simply adds each pair of consecutive fields to show as a frame. So the canvas shows this interlaced clip exactly the same as it shows the original progressive clip.
Editing effects applied to this interlaced clip could conceivably break the pattern and make something where the interlacing shows itself in the viewer. Speed changes could, and really should, do this. But FCP's speed changes don't seem to. An example of an editing effect that would certainly make the interlaced clip look interlaced in the viewer is this: "omit the first and last fields of the clip" (a sophisticated way to convert field dominance). But FCP doesn't include that effect.
For a digital video clip, being progressive or interlaced with this or that dominance is represented by an instruction in the file header. FCP effects seem all to work on frames, not fields. FCP effects seem to ignore the interlace instruction in the file header. A humorous example is when you apply the FCP "shift fields filter" to a progressive clip. Why not?
Dennis Couzin
Berlin, Germany
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