Maths of Slo Mo
 

Hi all, Im working on a 16mm music video and planning to shoot at a frame rate of 33.3fps to acheive a slight surreal edge

Im wondering how to calculate exactly how much the song needs to be sped up so the band can give a synced performance as we shoot.

Cheers, ewan.

24 (or 25) FPS---------------100
____________ X ______________

33.5 FPS--------------------1

Ignore the dashed lined between the numbers. Spacing won't display the numbers correctly.

Formula for expressing percentage shortening of soundtrack playback time I think??? but please check with somebody else - don't take my word for it as I failed maths from Year 5 onwards.

Is your camera motor still xtal sync at the higher frame rate?

How about this:

Ok video is 25fps...that should make 33.3fps about 33.2% faster than 25fps.
(33.3 / 25 = 1.32 -> 33.2%)

..that means if its done right, the resulting song length should be:
song_in_seconds * 0.668 = 33.32% faster song in seconds
(1 - 0.332 = 0.668)

..but don't quote me on that ;)
If I where you I would just do a quick test!

cheers

//O.