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I never thought about this, but what if you shoot at 30 fps and want to produce 24? How do you map 30 onto 24 time-wise? In 30, each frame lasts 33.33ms. In 24
by clnq 3y ago
I never thought about this, but what if you shoot at 30 fps and want to produce 24? How do you map 30 onto 24 time-wise? In 30, each frame lasts 33.33ms. In 24 it’s 41.66. So if the first frame is synced, the second frame of something captured in 30 and transformed to 24 would show up 8.3ms too late. The third - 16.ms, and so on. It’s not possible to properly sync video to 24fps if it was shot at 30 without interpolation, right?
- Kirby64 3y agoIt’s commonly done the other way, actually. Converting 24fps to 30fps for converting film (typically shot at 24fps) to TV broadcast ready, which is 29.97 fps in the US/NTSC region. That said, you can go the other way. Basically, you interlace certain frames. Wikipedia has a great article on this. https://en.m.wikipedia.org/wiki/Three-two_pull_down#2:3 https://en.m.wikipedia.org/wiki/Three-two_pull_down#2:3
- clnq 3y agoThanks. Then I suppose it doesn't matter if it's 30fps to 24fps or the other way around, the process is probably similar - either interpolation or interlacing. And that brings up an interesting point - after such a process, is it possible to produce clear visuals on each frame? The image [0] on the Wikipedia article illustrates my question. [0] https://en.m.wikipedia.org/wiki/Three-two_pull_down#/media/File%3A32pulldown.svg https://en.m.wikipedia.org/wiki/Three-two_pull_down#/media/F...