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duplicate frame working in 720p 50 fps problem
Hi, i’m having problem working with this format.
Working a sequence in 720P 25 Uncompressed 10Bit 4:2:2.
Copying the sequence in a new sequence 720P 50 Uncompressed 10Bit 4:2:2.
Each frame is duplicate to create 50frames that great but, before each cut, the frame is tripled and after the cut is single.Looks like this: 11 – 22 – 333 – 4 – 55 – 66 – 77
So when we do a interlaced digital betacam from this tape we get that result:11 – 22 – 33 – 34 – 55 – 66 – 77 which is not good.
Any idea?
My computer specs :
Apple Quad-core intel xeon 2X 3ghz
9GB Ram
OS: 10.5.7
FCP: 6.0.5
Card: Aja Kona 3 (firmware 6.0.2)Guillaume Mayrand
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7 Replies
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Why put it in a 50fps timeline first? SImply do a real time downconvert to Digibeta and you will get 25psf.
Jeremy
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Because at the end it will be send to a 720p 50 FPS HDSR tape
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[Guillaume Mayrand] “Because at the end it will be send to a 720p 50 FPS HDSR tape”
Your Kona card will add the proper pulldown. When you monitor your 720p25 footage, you are really watching 720p50. Look at your video output or frame buffer on the Kona CP. It says 720p50, no?
Jeremy
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first,
Thank you for your quick respond.
If I return to my main post, My first issue isn’t with the output but within the FCP timeline that add a 3rd frame before each cut (see my first post)
I understand that if I put a 25 fps timeline to a 50 FPS timeline it will double the frames but why add a 3frame before each cut?….Thank you
Guillaume Mayrand
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[Guillaume Mayrand] “My first issue isn’t with the output but within the FCP timeline that add a 3rd frame before each cut (see my first post) “
I don’t know, must be a bug of some sort.
[Guillaume Mayrand] “I understand that if I put a 25 fps timeline to a 50 FPS timeline it will double the frames but why add a 3frame before each cut?…. “
Not sure.
I wouldn’t let FCO handle the pulldown if it’s screwing up. The way I see it, you have two options.
Bounce the 25p file to Compressor and let it add the pulldown
Or simply let the Kona add pulldown in real time on layoff. No reason to do any software conversions.
Jeremy
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The thing is that we have to delivered in 720P50 and in digi beta, so we do the 720P out put first and than the digi beta from that tape. If we try to output directly from the 25fps sequence via the Kona in 50fps settings, it’s impossible to get the first frame in place. We are 1 frame off. If we tried to offset the output, since it is based on a 25fps we get the same result, but earlier. That’s why we decide to move the sequence into a 50fps so FinalCut will duplicate each frame and that’s it! But then we discover that it does that greatly but not before and after each cut. That’s weird. The only work around: export the 25fps in a QT Ref 25fps and reimport it into a 50fps sequence. Since we get rid of the cuts. It works.
but why ?
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[Guillaume Mayrand] ” If we try to output directly from the 25fps sequence via the Kona in 50fps settings, it’s impossible to get the first frame in place. “
A ha. The real problem. Have you contacted AJA about this?
[Guillaume Mayrand] “but why ?”
FCP has never been good at dealing with pulldown. Pulldown in 720p usually works well on the 60Hz side, but I have never tested 720p25/50.
If the hardware isn’t going to work for you, I’d go to Compressor.
Jeremy
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