Sync problem at post with Red Weapon and 688

6.30K viewsHardwarered timecode

Hi Guys,

I just finished my project last week. I found after i sync everything together, video and audio got slightly offset.  Camera was Red Weapon 8K, my recorder was sound devices 688. I jammed the tentacle from 688 everyday before we shoot and used tentacle to jam Red and i left tentacle attached with RED weapon. we shot on 24 fps.

At post, i found at beginning of the day, audio and video had 1 or 2 frame offset, and the end of the day, audio and video got around 12 frames offset. we normally shot 12 hours a day, and i didn’t jam tentacle in the middle of the shooting, just let it run for the whole day.

is anyone got a idea here or know what it wrong here? why i have the offset?

Thanks Guys


I was doning the exactly same way like you said. I have no ideal why sync got offset. I use tentacle Studio to sync and export xml to my Premeier pr cc 2017.


Genlock? There is no Genlock on the Tentacle. Only timecode.

The 688 should keep timecode for a few hours when turned off.

If the RED is turned off and is reading timecode externally ALL THE TIME then there is no problem there because the tentacle stays on.


I set the red genlock to be external. after I attached my tentacle to the red, the tc indicator on the monitor turned green.

however, my 688 and red got did not Keep running for the whole day, we powered off the red and 688 couple of times.


Are you sure that the Red is constantly looking at the timecode, or does it jam once and then runs on it’s own clock? My suspicion is that the problem somewhere with the Red.

In most cases a tentacle and a 688 would stay in sync within one frame for 24 hours. You can test that yourself as the 688 has a build in offset reader in the JAM window.