length of sync cables?

[asmischney]

Hello!
We have started testing out our optitrack system, and are beginning to get good results. We are having issues with the sync cables slowly pulling the cameras out of alignment, and ruining our calibration. right now the sync cables are pulled pretty tight from tripod to tripod. To fix this we are going to get longer cables so we can run the sync cable on the floor and take the strain off.

couple of questions though;
1. Do you have any length restrictions on the sync cables?
2. are thy simple RCA jacks?

thanks much for your time!

[VincentG]

1 - We have no length rescrictions, just the RCA specifications (I wouldn't go more than 50 ft. between conections......

2 - Yep, standard RCA

[asmischney]

thanks much!

[VincentG]

No issues......

[Jim]

Thanks for posting. We are realizing that we need to stock longer Sync RCA cables, 30' ones are coming soon to our online store. You can just take two 15' ones together, or a single longer one. I would try and keep it less than 30', as I have tested to that length, but up to 50 could work. You will know if it isn't working as your data will be terrible!

[leith]

The length is actually fine for most things. Since a USB cable can only be about 15' in length, you just make a cable holster consisting of two 15' RCA cables and 1 15' USB cable. Then you barrel the RCAs together in the right order at the hub and plug the USBs into the hub. It simplifies the cable runs as far as tangle and tension and makes setup go faster. Then, you're only left with the runs of USB to the hubs from the computer, and the sync runs from hub to hub.

Question though: is there eventually a limit to overall run length? Does the sync signal get repeated or amplified in the cameras? Or does the signal lose overall strength as it moves from camera to camera?

[Jim]

The sync signal is regenerated from each camera, but there is a propogation delay and signal reflection that can make the rise time long, so shorter is better. I think a 30' cable should be fine. The real length limit could be much longer, haven't tested it though.