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Interlacing progressive video for broadcast…
I shot an instructional video with my Canon XL-2 using a 30p frame rate, however, I now need to make that video interlaced for broadcast. Is there an easy way to do this right in FCP? I should say that I’m running FCP 4.5 and I have Motion at my disposal. Sorry if this is a very basic question. Thanks.
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7 Replies
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Any particular reason you need it interlaced? Just because it is for broadcast doesn’t mean you need it to be interlaced.
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Really? I was under the impression that all broadcast video had to be interlaced.
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Your 30p is really 60i that looks like 30p. The 30p is effectively embedded in a 60i video stream, and hence you have nothing to worry about.
You can convert progressive video to interlaced, and this is done to restore old TV that only exists as telerecordings, but it is a very specialised and time consuming process, and a process you do not need.
Graeme
– http://www.nattress.com – Film Effects and Standards Conversion for FCP
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Your 30p is actually psf (progressive segmented frame).
This means that the frame is composed of two subfields which contain the same moment in time divided into an odd and even set of fields. The image is indeed progressive but the vtr is tricked into thinking it is interlace because of the two fields.
Interlace contains two fields created from one frame but each field contains two moments in time separated by 1/60 of a second.
So in your case you do not need to do anything to work with the footage in FCP.
Keep in mind when shooting in 30P you will have more motion blur than when in 60i mode because of the actual exposure time at the CCD 1/30 sec versus 1/60 sec. You can reduce the motion blur in 30P by activating the camera shutter and setting it to 1/60 when shooting in 30P mode.
Tony Salgado
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Thanks for the info Graeme. So, I can just print to tape and I’ll be fine for the broadcast? By the way, I just got your Film Effects package and am very happy with it.
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[Quote]
Your 30p is actually psf (progressive segmented frame).This means that the frame is composed of two subfields which contain the same moment in time divided into an odd and even set of fields. The image is indeed progressive but the vtr is tricked into thinking it is interlace because of the two fields.
Interlace contains two fields created from one frame but each field contains two moments in time separated by 1/60 of a second.
So in your case you do not need to do anything to work with the footage in FCP.
Keep in mind when shooting in 30P you will have more motion blur than when in 60i mode because of the actual exposure time at the CCD 1/30 sec versus 1/60 sec. You can reduce the motion blur in 30P by activating the camera shutter and setting it to 1/60 when shooting in 30P mode.
[End Quote]What he said. One other thing, 30p with alot of motion and pans can look pretty stuttery. If that were to happen you could try to do a time stretch at 50% speed using compressor or Twixtor, ect. Something witch does optical flow analysis. In effect making a 60p version of the clip, and then interlace that. It would be rather time consuming and there’s a really good chance it wouldn’t look right but it’s possible.
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