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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Timecode drift

D

Drew Suppa

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Why does timecode drift occur when external modules are plugged into the RED? We have 2 bodies and a smart slate synced to sound, but A Camera is independently drifting from sync... by the end of the day, the camera is about 4 seconds behind slate.

Anyone have some rationalization for this that I could be missing, or are the modules losing power when the bodies are turned off?
 
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Timecode

Timecode

Why does timecode drift occur when external modules are plugged into the RED? We have 2 bodies and a smart slate synced to sound, but A Camera is independently drifting from sync... by the end of the day, the camera is about 4 seconds behind slate.

Anyone have some rationalization for this that I could be missing, or are the modules losing power when the bodies are turned off?
Click to expand...

As a general comment, it doesn't drift.

So can you describe more precisely how you have these items connected, and what your sync procedure is at the start of day and during the day?
 
We have Genlock boxes from sound... and somehow A Camera has drifted. B Cam has no issues and has stayed sync'd.
 
Timecode drift?

Timecode drift?

We have Genlock boxes from sound... and somehow A Camera has drifted. B Cam has no issues and has stayed sync'd.
Click to expand...

Drew, I'm not trying to pick on you in any way, and I do believe that what you are saying may well be true....

However, if you could provide an answer to the specific question I asked rather than re-stating the issue, we will be in a much better position to help you.
 
Sorry Stuart; I've been racing around with a couple of things on set.

We have the timecode cable plugged into our genlock. I haven't been able to check to see if the TC output is enabled. That would make sense to our issue, and explain the gradual delay for our sync.
 
Timecode drift?

Timecode drift?

We have the timecode cable plugged into our genlock. I haven't been able to check to see if the TC output is enabled. That would make sense to our issue, and explain the gradual delay for our sync.
Click to expand...

As Genlock is a term usually used to describe a video frame sync signal, that's not too much help I'm afraid.

Are you syncing the camera to another device such as a LockIt! or are you trying to sync the other device to the camera ?
 
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Could A+B cameras be fitted with different series of audio boards?

I had some drift issues with earlier firmware builds, but I think it was a genlock issue. I've not experienced any drift with either generation of boards with v17. Although I have noticed Red can be picky with the type of TA5 cable used. Have you tried swapping cables with your TC feed?

With firmware v17 build 3.4.1 me and a sound recordist ran some tests for a TV show we were working on at the time using an Ambient Lock It box with a Sound Devices 744 audio recorder as a TC Slave. The camera served as TC Master. Using a Denecke digi slate, we found that there was a variable 5-8 frames difference between picture and sound. When the genlock symbol stayed on, it was always consistent. But there were occasions when editorial reported a massive difference. This was probably down to power cycling.

We were inputting audio as guide track only on just channel 1 with a Sennhesier EW series radio receiver. We both assumed it was due to A/D conversation delays. It would be good to have an audio offset in the menus, as per Sony SRW1. At the time, the main camera was fitted with the older v1 audio board. It has since been upgraded.

With v17, I'm one who disables audio whether production / editorial request it or not due to the occasional to sometimes far too frequent Audio Error messages at Post write. Hopefully, the stability issue of Audio Error messages will be eliminated with release build 20, whether you chose to have audio enabled or not.
 
Now that it's lunch, I had time to get in there and pull off the cases on the devices and type their manufacturer and model info.

We are syncing the cameras to external devices, specifically two Ambient Clockit's. I don't know what audio is using specifically. Both cameras are Build 17 and this issue might be similar to David's above.
 
Drift

Drift

O.K, so do both cameras show the Chain Link icon in the UI and TC EXT on the rear of the LCD ?

Are the Lockit's both set to the same dip switch settings - and that is?

And have you shot any variable frame rate footage ?
 
Sorry I left you hanging Stuart; the culprit was that the camera was outputting it's signal to the Clockit! and then trying to send it back to itself... a simple click on a System menu disabled it after someone turned it on by mistake.

I'm confident this fixed the drift issue, but I'll reconfirm with post later today.

Thanks for your help.
 
Well in our latest 3D shoot we saw 1-2 frames drift after about 30-40mins....

We were using an aja gen 10 for genlock and had the sound guy jam the cameras after every battery swap and whenever he could.

We not syncing camera off the TC anyways so it's not a big deal 1-2 frames as long as we are within the same second or so.....but that might change.

Your saying they should not drift? Well ours are drifting for sure.

We have lock icon and chain icon and I can see drift after while.....

anyideas ?
 
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