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Controlling a tempo strobe for recording w logic pro 9


scottymac

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I aplolgise if thsi is answered somewhere else, however after extensive search I could not find it.

 

All I'm looking to do is export the click track to a strobe or trigger light, so the drummer in the studio can visually follow the tempo. I'm sure there are dozens of studios who are doing this. I'm just at a loss here. I'd consider external gear, ( as in the recording light we have now ),

 

If anyone has any info it would be greatly appreciated.

 

Happy Holidays to All

 

Scott

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I think the answer you are looking for uses SMPTE time code. Ive never worked with lights, but I'm pretty sure thats how you sync it up.

 

I had a tech class here at Berklee and they were talking about timecode one day... here are my notes

 

NOTES

 

The time code we're used to is called BITC for burn in TIMECODE, aka visual TC. That TIMECODE is only for humans.

 

We also have LTC for longitudinal TIMECODE or linear TIMECODE, which is an audio signal that gets embedded in tape for example using an LTC generator. Video tape has two channels for audio and it goes in one. This can then be converted to MTC

 

MTC is midi TIMECODE, when the tape degrades the signal can drop out and the sequencer gets lost. To compensate for this they invented VITC vertical internal TIMECODE, its information that's in-between frames vertically

 

Running video on another machine, the video would send midi TIMECODE to your sequencer to sync

 

Lights and shows run in midi time code, usually 30fps

 

and why not... here are my notes on frame rates!

 

29.97 drop frame: First two frames skipped every minute, except on minutes ending in zero

 

30 fps black/white tv

 

Interlaced video has two fields, odd and even numbered lines, the frame rate is half the field rate

 

They used to use the incoming electricity AC as a clock source for the field rate. The electricity coming out of the wall in the us is 60 hz

 

When they invented color television something happened to tv sets, the tv needed to show more information. When the color signal was added into the video signal. This extra info caused some interference or resonating or something which would cause a loud humming, the component that fired the lines across the screen to be exact. They had to fix this. Instead of replacing tv sets, they altered the video signal which was flickering at the same speed, ever so slightly, down by a factor of .001 from 30 which fives you 29.97

 

This was probably organized and done by SMPTE society, or the NTSC national television systems committee.

 

The problem with 29.97 means that the seconds go by in TIMECODE are wrong because they go by real seconds. This resulted in drop frame. In drop frame you drop 108 frames every hour.

 

Pal is 25 fps

 

NTSC color video means 29.97. It is used in north America, brazil, Japan, south Korea, the phillipenes, and a few other places like Guam and American Samoa where the us has been present after world war 2. It was invented in 1953.

 

In 2009 ATSC became the new standard which includes high definition material. ATSC includes everything NTSC and is backwards compatible. It is only used in north America. Japan has their own standard now too.

 

A new frame rate that's been appearing over the last few years, is 23.976 (23.98). Tis is the framrate of most commercial DVD. Tis is 24 fps slowed by a factor of .001

 

Games have cut scenes and can be any fps.

 

Film is 24

 

Pal has been replaced by dbd

 

an "Academy leader", is exactly 8 secs long. Has sync pop 2 seconds in front of the first frame. On 2, you see "flash frame" for one frame, goes black for other two seconds. First frame of academy leader is called PICTURE START, exactly 8 seconds before first frame of action. Sync pop gets lined up perfectly with flash frame, gives visual indication of sync between audio and video.

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I aplolgise if thsi is answered somewhere else, however after extensive search I could not find it.

 

All I'm looking to do is export the click track to a strobe or trigger light, so the drummer in the studio can visually follow the tempo. I'm sure there are dozens of studios who are doing this. I'm just at a loss here. I'd consider external gear, ( as in the recording light we have now ),

 

If anyone has any info it would be greatly appreciated.

 

Happy Holidays to All

 

Scott

 

:roll:

 

Is the drummer recording with the rest of the band? Is he wearing headphones?

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