Re: sync 16mm projector to external sound device

From: Robert Schaller (email suppressed)
Date: Sat Jun 21 2008 - 19:57:14 PDT


I've done exactly the same thing with LTC on a double system projector and
both a DA-88 and a Digidesign slave driver, and concur that these approaches
work great but they're rather less than compact. I saw the film-o-sync site
and am planning to try it -- thanks, Zach, for doing that and letting others
use it; it's a great thing -- but since the subject has come up, I'd like to
ask Zach a question:

    Is the signal being generated a sine-wave like tone? Does your software
support a square wave, or a pulse? What kind of signal does it expect? I
don't have Max/etc., so I can't easily tweak the source code. I am hoping
to add the magnet(s) or a pulse generator to the shaft of a Pageant, and got
the impression from the instructions that you describe magnets attached to a
rotating disc at the end of a shaft. I wasn't clear about it, and since
you're here, could I ask you to clarify a little? It would be certainly
easiest to use the software as is, and not have to tweak it!

    Thanks,

    Robert Schaller

On 6/21/08 5:11 PM, "Zach Poff" <email suppressed> wrote:

> I made some (free) software called Film-O-Sync that does this. We use it
> frequently with students at Cooper Union Art School and it works great. You
> add a DIY tachometer to the projector and load your soundfile on a
> Macintosh. You have to watch the 2-pop and trigger the sound in sync, but
> afterwards the software will chase the projector's speed changes (note that
> there's no absolute time reference like you would get with LTC). Full
> instructions and the download are here:
> http://www.zachpoff.com/site/software/software.html#filmosync
> It was made in the MAX/MSP/Jitter visual programming environment, and the
> source files are included. So if you have access to MAX you can tweak it
> however you want.
>
> Also, I've heard that there are lots of problems getting an LTC track to
> "stick" to optical, since the fidelity is so low and the projector
> alignment is quite variable. I have a friend who striped LTC on mag and
> used a double-system projector to drive a DA-88 digital tape machine for
> surround. It worked great but it weighed 100 lbs!
>
> ProTools would work, but only with a TDM system and the "slave driver"
> rackmount interface. Not cheap.
>
> Good luck!
>
> -Zach Poff
>
>
> __________________________________________________________________
> For info on FrameWorks, contact Pip Chodorov at <email suppressed>.

__________________________________________________________________
For info on FrameWorks, contact Pip Chodorov at <email suppressed>.