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XDCAM HD Slo Mo Question
Hi everyone,
Sorry if this has been discussed before, but I couldn’t find it!
I use a XDCAM HD 350, running in PAL. For slow mo, I run 25p overcranked to 50. Thus 50 FPS.Someone suggested I try NTSC at 30p overcranking to 60. Thus 60 FPS for a slower motion.
I ran a test, bouncing a rubber ball from a predetermined height and recorded the results. I then placed the clips on time-line and lined them up from when the ball enters the frame.
To my surprise, both clips run in parallel, the ball bouncing at the same point on the time-line in both clips. How is this so? Am I a plonker for not understanding that 50 fps is the same as 60 fps in NTSC land?
Many thanks,
Simon.
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5 Replies
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If frame rate is cranked to double actual frame rate then you would get half speed when played back at normal frame rate.
30/60=1/2, 25/50=1/2. both are .5 normal speed
Now if you want slower motion try 24P cranked to 60.
24/60=6/15 or .4 normal speed
Olof Ekbergh
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Yes, I understand that but I am playing back at 25 fps on the timeline so a clip recorded at NTSC 60fps, should be playing back slower than half rate on a PAL 25 fps?
But thanks for the 24 at 60 hint. Didn’t think of trying that. -
It must have to do with your NLE’s interpretation of the footage, are you using FCP?
If you use AE and play frame for frame then it would be slower.
I have not used 25P yet, can you over-crank that to 60fps?
Olof Ekbergh
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I think you’re right. I’m using Vegas Pro and have posted on that forum too. Strange but good to know I’m not going mad (yet).
25p only goes to 50fps.
Many thanks,
Simon.
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On my EX1 720p25 goes to 60p for S&Q motion…
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