LCD/Pasma delay's and audio layback to digibeta

[danny prent]

Hey everyone,
I realy realy want a nice big flat screen in my studio.
All the post i found were about quicktime video but i'm using an avid mojo 4 digitizing and playback of video

My biggest fear is if i use the "video sync offest" function in pro tools my layback to tape is out of sync with my video
Anyone had this problem or has any tips fore me????????

Tanx, Danny

[bryston]

We use 42" Panasonic Plasmas, and you have to set the video sync offset by 2 frames when playing back video recorded with the mojo. The only way to watch a layback in sync would be to delay the audio output you feed to your speakers.

[soundguydave]

The digitized video gets offset, not the audio. so if you are laying back to tape with timecode and picture, everything will lock up. If you are laying back audio and picture to a new tape, you would need to remove the offset each time. I use a sharp aqous and the delay is less than 2 frames.

[bryston]

Yes, but if you are watching your layback off tape(not the mojo) to the LCD/plasma, there will be no video offset. You must delay the audio to the speakers (only). We watch the video off tape during layback with the caracter gen on to watch for possible drop outs on the d-beta.

[Chief Technician]

We use 42" Panasonic Plasmas, and you have to set the video sync offset by 2 frames when playing back video recorded with the mojo.

This will be different if you use a different type of input. Also, note that the AVID video offset is only in frames. If the latency of your plasma is 2.5 frames, you have to pick one - 2 or 3 frames of offset.

[Phil Jeffers]

I can't see the problem if PT's is chasing TC off the Digi-Beta. The QT might be out slightly, but the sound will be in sync with the tape. Do you mean just for playback?

[Chief Technician]

I'm not certain of what you are asking or whom you are asking to respond. If you have a Panasonic plasma, and you measure the delay at the composite input, and then measure the delay on a different type of input (such as HD-SDI), the delay values will be different. If PT is chasing a Digi Beta, sure the sound will be in sync with the tape, but will the sound be in sync with the video? Not on a plasma display, unless you delay the audio to sync with the plasma.

[JKD99]

Sounds like 2 different scenarios, right?: Obviously, with a digitized QT, there can be a sync offset on the VIDEO end to advance the picture to compensate for the plasma delay, and the audio stays as-is. With "LIVE" video in a DigiBeta layback session, the only way to watch it in sync would be by delaying the audio, as advancing the DBeta video while laying back is impossible (and of course, any guide audio already on the DBeta would also have to run through the same delay). So, to be able to do both (ie, QT playback AND a live feed from a VTR) with the SAME setup, the only way is to delay the audio.

[danny prent]

Tanks evryone,

Al thge reactions realy helped me and let me realise the only way to do this is by deaying my monitoring.

This is probably the best way i think.

Danny

[jodyspencer20]

Danny I know exactly what issue you are addressing here. Have you got an accurate method of delaying your audio to your monitors to compensate for the plasma/lcd lag?