Timecode issue with 3D Epic

[Dave Winder]

Almost forgot. Playback is not synchronized between the cameras.

[David Barlow]

Yeah. Playback of high speed shots a half second out of sync can be quite surreal. However, seeing the high speed played back immediately is invaluable.

[Arnaud Paris]

Can somebody confirm that the moded Denecke SB-T for 3D is a valid option for high framerate on Epic as a factor of 25fps?

Thanks

[David Cole]

I have many hours of 3D on my Scarlet rig using a modified Denecke SB-T and it has been ROCK SOLID for sync and timecode.

[Arnaud Paris]

Thanks David, but since you're using it with Scarlet I imagine you don't go in really high frame rates.
Is somebody using it with Epics up to like 250 or 300fps with rock solid results as well?

[Ross Isaacs]

The issue with genlock signal is that a 'T' essentially doubly terminates the signal, cutting the level in half. This leaves it very close to the lower threshold required by the circuitry in the camera. Depending on the genlock source this may or not work. Therefore, RED does not recommend using a T.
An Ambient Lockit for example becomes marginal. But, Ambient does have a mod available that provides two genlock output connectors. A Lockit with a T often works 'OK' going straight into the 3BNC-lemo cables. But its not guaranteed.

As for timecode alignment, the cameras are not guaranteed to start record on exactly the same frame. Using the GP Input as a trigger with a single button T ing to both cameras will get you the closest you can, and it is very close, as in a couple of frames. RCX will then usually line them up automatically by timecode. Framerates off the project rate will have more variation. Using a slate is recommended. Using the GigE cable to control record on both cameras will have more variation in the start of the record since there is delay to relay the commands to the slave camera.

High framerate synched recording is supported. Its not a fluke.

I am just about to purchase an AMBIENT ACL 204 for Time code generation and syncing 2 x Epic Xs on a 3Ality Technica Atom rig. I have the following cables from RDCC. Can you tell me if I will require any other cables or accessories to make this work?
1 X Ambient ACL 204
1 x Master/Slave GIG-E cable (4')
2 x 3BNC-To-OO Sync cables

[Dave Winder]

I dont have experience with the 204, but since they are purposefully supporting dual load, I would say this is the correct shopping list with a few additions needed.
You will need the T adapter for the genlock, and two of the TC lemo to BNC adapter cables (not a RED item), or one cable and a T. Timecode handles the T-ing better. like these
http://www.ambient.de/en/produkte/am...l/ltc-out.html
http://www.performanceaudio.com/buy/...s/XL_LB2/27072
I have used the second one.

[Ross Isaacs]

I dont have experience with the 204, but since they are purposefully supporting dual load, I would say this is the correct shopping list with a few additions needed.
You will need the T adapter for the genlock, and two of the TC lemo to BNC adapter cables (not a RED item), or one cable and a T. Timecode handles the T-ing better. like these
http://www.ambient.de/en/produkte/am...l/ltc-out.html
http://www.performanceaudio.com/buy/...s/XL_LB2/27072
I have used the second one.

Thanks Dave

I believe some of those other cables come with the Ambient 204.

[JP Perry]

We have found the old SB-T and the new upgraded one to both work the same. Are we just getting lucky with the old one? Trying to decide if we should upgrade all units or keep going with what is already working.

[Dave Winder]

In my opinion, you are getting lucky. If you can, I would recommend upgrading so you are ensuring the proper signal levels.