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  #1  
Old 07-17-2024, 01:53 PM
subwoof subwoof is offline
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Default 30 fps to 24 ps convert

Am I wrong, or are audio files mixed at 30 fps the same speed as 24 fps, and therefore the sync should be the same?
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  #2  
Old 07-17-2024, 02:12 PM
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Default Re: 30 fps to 24 ps convert

Video is synced by frames (leading edge), audio is synced by samples.

For 48kHz sampling rate and 24fps video, each frame contains 2000 samples of audio. For 48kHz sampling rate and 30fps video, each frame contains 1600 samples of audio.

Both footage should play at same speed on their own, but if you need to get both of the video working together, you need to either convert 30fps to 24fps or 24fps to 30fps, so both are the same when you use them.
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  #3  
Old 07-17-2024, 08:46 PM
fork-media fork-media is offline
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Default Re: 30 fps to 24 ps convert

if you find you are losing sync due to a frame change in video, I seem to remember having to create a new project then importing the old one. and in the import options you can apply pull up or pull down to solve..
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Old 07-17-2024, 09:56 PM
BScout BScout is offline
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Default Re: 30 fps to 24 ps convert

Seconds are seconds no matter how many frames are going by.
That is, as long as no one is speeding up or slowing down the frames but are actually converting them too. (The UK used to run 24fps at 25 fps with no change so the movies were a bit shorter and the pitched shifted)

The 0.1% pull up/down (24/23.976 or 30/29.97) was/is different because it was running the frames faster or slower which is why sync would go out but not the same thing as 30/24 where the fields/frames are divided/multiplied to cover the same length of time.
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  #5  
Old 07-19-2024, 12:38 PM
subwoof subwoof is offline
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Default Re: 30 fps to 24 ps convert

Thanks for your input!
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Old 07-20-2024, 02:06 AM
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Default Re: 30 fps to 24 ps convert

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Originally Posted by subwoof View Post
Am I wrong, or are audio files mixed at 30 fps the same speed as 24 fps, and therefore the sync should be the same?
Yes but true 30 FPS is for B&W TV. Colour TV (NTSC) created the frame rate of 29.97 so I'd check if your audio files were mixed at 30 FPS or 29.97 FPS.
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Old 07-20-2024, 04:33 AM
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Default Re: 30 fps to 24 ps convert

Yep, NTSC sucks in so many ways. Glad US got 720p faster than EU, but in here PAL (576p) was already so much better we could wait for 1080p.
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Old 07-23-2024, 10:24 PM
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mgoorevich mgoorevich is offline
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Default Re: 30 fps to 24 ps convert

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Yep, NTSC sucks in so many ways. Glad US got 720p faster than EU, but in here PAL (576p) was already so much better we could wait for 1080p.
This advantage is derived from domain power utility.
Here is PAL world, we have 50 Hz 220V which is much better than 60Hz 110V (in US)
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  #9  
Old 07-24-2024, 07:13 AM
smurfyou smurfyou is offline
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Default Re: 30 fps to 24 ps convert

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This advantage is derived from domain power utility.
Here is PAL world, we have 50 Hz 220V which is much better than 60Hz 110V (in US)
The only real difference is it takes our kettles twice as long to boil
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Old 07-24-2024, 07:54 AM
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Default Re: 30 fps to 24 ps convert

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The only real difference is it takes our kettles twice as long to boil
Whi is telling you bedside stories?
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