HVX Music Video Synch 18 fps, 24fps

[nathan_collett]

Hi,
Im shooting a performance music video with playback, and its my first time shooting such a project on the HVX. Im planning to shot at 24fps for most of it, but also under cranking from 18-20 fps to give the piece more energy. Other than trying to synch in post, is there an optimal way to playback the song on set, to ensure it will synch up? I am assuming i should speed up the footage...but am not sure what other settings i should be aware of.

Also for the 24fps footage, at what rate and speed should i be playing back the song? Its originally on a cd 44.1 khz. Should I upres to 48khz and play back at that rate? how much should i slow down/or speed up to maintain sych at 18-20 and 24fps. Thanks so much for your help!
Best, Nathan

[kenn michael]

You'll need to process the song before playing it on set.

The easiest way is to bring the audio into Final Cut (or whatever editing software you're using) and do a speed change on the song.

For 18fps have the song processed at 75% normal speed.
For 20fps have the song processed at 83.3% normal speed.

Export both versions from the edit software then burn onto a CD. The hard part will be finding sync points in the footage during editing since there's no on-camera audio recorded when shooting off-speed.

[J.R. Hudson]

Nice answers Kenn

What is the math on this technique ? 20fps is 83.3 % of 24fps ?

Is there a formula too this if you use the Video playback at 'X' ?

Like

X fps = ?

(I'ts early)

[Barry_Green]

Beware that 18fps and 20fps are not exactly 18 or 20. Look in the manual or the HVX Book to find the exact frame rates and be sure to base your calculations of the exact rates.

[palmerman]

ALso... only way to sync is to use a "Smart Slate" that gives visual timecode to your off frame rate music track. We do it all the time in film Music Videos.