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video sync offset. 3 frame delay on renderer.

Have you attempted to send a 2-pop to the renderer and to the output bus at the same time?  Im getting a 3 frame delay on the renderer.  This is not fixed with video sync offset It makes it worse. 


I've confirmed the same with another persons system. 


*Ive recorded the pops with my sony d50 and can confirm the delay is about 2.75 frames  

WAV
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its out by 3 frames. Confirmed by eye and then by catchin sync. 


I believe video sync offset does affect internal video.  I just posed the question to avid directly. We will have that answer shorty.


Regardless, When I set the video sync offset to 11qf catchin sync reports even greater latency. 5 frames or so. 

I've also confirmed the issue on another persons system. 

while im waiting on hold for avid to give me a definitive Ive added 24qf to a different session and can clearly see the video is delayed.  So Im 100% certain that video sync offset affects internal video. 

ive aso used video sync offset in sessions for over a decade. 

avid confirms video sync offset works on internal video. 

Ok so after some inverstigation it seems Video Sync Offset is designed to compensate for delays in the video chain not the audio chain. If you are adding 11 quarter frames of video sync offset to an audio delay of 3 frames then you are pushing the video further towards 00hr thus increasing the overall latency of the system.,


To compensate for the audio offset induced by the renderer try putting the 11 frames as a negative video offset.


So -11 rather than 11.

It seems this behavior affects video after AVE introduced but not before i.e. PT10 with QT engine did not offset internal video but did effect external devices.

ok i will give that a try and report back. 

ok I think using negative values fixes that. Strangely I'm at -2qf???  However in my testing I've found another issue. Its easier to show you a video of this but basically the object tracks and the bed tracks have different latency.  the beds having greater latency then objects...


https://www.youtube.com/watch?v=m8_Jb1Z_cM4



and just for more info the bed tracks go to a aux bus with only the send on it.  The object tracks are going to a aux but as in the templates.  No other plug ins are in the chain with either of these channels. 

Yes, I've seen this before but oddly the other way round, objects more latency than beds. I don't have a good answer for you on that maybe one of my counterparts will. 


Glad the Video offset issue is resolved for you. 


For other users who may come across this and also have video hardware attached the Video Sync offset will operate on your Video Hardware but not the "Desktop" video so when putting in offsets you will see that the desktop video behaves differently than your video card outputs. 


That being said the calculation would be an overall so if for example you have an 18qfr delay in your projector chain then adding in 11qfr delay (as in this example) to the chain will result in an overall Video Sync offset of 7qfr not 29qfr.


Now to get that Bed/Object delay figured out!


Is it possible to place Time Adjuster plugins on all of your object tracks before the Send plugin to compensate?

sure.  I can.  My worry right now is if this number isnt constant. As I was at 2.5 frames of delay on the system.  Then wiping out the auxes to the local renderer for the beds and bringing them back has changed this. I will monitor for a few days to make sure it wont. 


Also video sync offset was working for me in 10 on desktop video ;)

Let us know if you experience any issues with the renderer. 

https://youtu.be/22UkryrChxI


Is the z plane supposed to be moving in this mode? 

yeah these panners z plan is broken is seems.  I have another set that was working and now the z plan is disabled? Clients in 10 minutes

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