TC sync with Sony PMW-EX3 XDCAM EX cams

[Richard Ragon]

I might be working on a Reality TV show, with several Sony PMW-EX3 XDCAM EX cameras.  I'm wondering about TC syncing..

Does anyone have any experience working with TC on these?  Right now the work flow is to set up a master camera, then the other cameras sync there TC via the master (A cam).  Currently, I'm running sound (2 chan) to the Master.  But, In the future, if I wanted to record tracks separate.. I'm thinking of also sync'ing with their TC.

1) Is it better to have all the cameras sync to the TC on my recorder?

2) Or should I set up my recorder as the slave, and also use the master cam?

3) If we free run any of these?  Will they go out of sync, or have sync issues? Can we set everything at 29.97?

4) Would it be better to do a master sync equipment, and sync to that?

Thanks everyone..

-Richard

[John Steigerwald]

1) Is it better to have all the cameras sync to the TC on my recorder?

Assuming you can jam these cameras from external timecode, I would.  Doesn't really matter, but you might as well be the master. 

Chances are you have the more accurate clock anyways.

2) Or should I set up my recorder as the slave, and also use the master cam?

Only if you needed rec-run, at which point you'd (likely) be hardwired.

3) If we free run any of these?  Will they go out of sync, or have sync issues? Can we set everything at 29.97?

Really depends on the drift of that camera.  You could always jam lockit boxes and velcro them to the cams.

Again, that depends on how they handle ext sync.

4) Would it be better to do a master sync equipment, and sync to that?

See #1

/$.02

EDIT: Just looked up that cam, it does have BNC TC in.  Jam them all to your recorder and off you go.  Only issue is drift.  Worst case, they all get lockit boxes.  Nice to see proper TC finally showing up on the dinkycams...

[Richard Ragon]

EDIT: Just looked up that cam, it does have BNC TC in.  Jam them all to your recorder and off you go.  Only issue is drift.  Worst case, they all get lockit boxes.  Nice to see proper TC finally showing up on the dinkycams...

Awesome..  We'll try the JAM to my recorder, and see how bad they drift after about 4 hours, then..

They haven't set a TC yet..  If this is set to go to TV, shouldn't it be 29.97?  Or do these cams have something funny going on with a weird TC or weird frame rate??

Thanks!

[Geluidloopt]

Hey,

i'm doing a show with 3 of these EX-3s and our modus operandi is a lockit on each camera, 25fps (thank you PAL-world!) and it syncs up perfectly, no complaints from post!  I haven't tried jamming them to check the drift, so can't really say anything about that.

They have all the regular tc frame-rates, so no varicam cross-jam weirdness here!

greetings

Marijn

[cmgoodin]

Slightly off topic but I just bought a Panasonic HD AVCCAM AG-HMC150 which records to very cheap SDHC Ram cards.

1/20th the price of P2 Cards.  I think we are going to see a lot more of these "ProSumer" HD Cameras especially on Docs and Corporate stuff.   

I was surprised to see that it does have a way to jam to LTC TC and to  Output LTC so you can jam other cameras or the Recorder.  It however only is a temporary output when running in Free Run TC.  It Uses the Composite Video Output to send and receive the LTC from the Internal Generator when a Menu Setting is set to Master or Slave.   You must leave this mode after Jamming since the Video output needs to revert to it's normal operation.

I will be dong some accuracy testing in the next week to see how much drift the camera has and how it does when batteries are changed etc.

------Courtney

[Philip Perkins]

None of those small cameras will hold jammed frame-sync for very long on their own.  If TC is the way your posties want to sync, then the Lockit/SBT jammed to your recorder is a good way to go.  We often do much more "casual" sync w/ these cameras for shows that don't generate as much footage as yours will (drama, concerts etc), ie "3-2-1-GO" type jam syncs and TC slates.  But your show should really do some testing before the boat leaves the shore, esp if this is to be a "rolling" series  that is broadcast while you are still shooting.

Philip Perkins

[Richard Ragon]

I found this..

http://www.denecke.com/Products/tcgenerators/tcgenerators.htm#SB3

Looks like Denecke has a 500 dollar lock box. Runs on 2 AA batteries, this might be the ticket for 6 cameras!

What do you guys think about these?

-Richard

[Philip Perkins]

The SB3 is a different animal from an SBT or Lockit.  The SB3 is a good stable TC generator (TXCO) and makes word clock of the sort needed for digital audio work (ie 48k, 44.1k etc).  The Lockit and SBT make good TC but also make SD and HD video sync signals as well.  For real frame sync between cameras, you need both of these to make sure the frame edges of the signal and TC on all the cameras are aligned.  In general, it isn't a great idea to send continuous TC to a video camera without sending it sync that is locked to that TC as well--in addition to drift you can end up with video errors such as the dreaded "green flash".  That's why that other show that was mentioned in this thread was using Lockit w/ the EX3s, I bet.  The SB3 (or SB2) would be fine to jam those cameras to, but if the cameras then run on their own internal clocks (not very accurate) there will be drift between them.  I'd REALLY recommend that you caucus w/ yr posties on this soon--there are lots of cool creative and cheap ways to do what you want to do, but everyone has to be on board with them and you really should do some full up tests.

Philip Perkins

[cmgoodin]

I agree with everything Phillip says, but one possible use where the SB3 is well suited is the situation for cameras that don't accept a continuous time code input and Genlock or where the editor or post stipulates that the cameras must only use REC-RUN time code. (bad idea but old ENG habits are hard to break).  On many of the Pro-Sumer HD video cameras like the Panasonic HVX200 and Sony EX1s  people are putting LTC onto one of the Audio Tracks for decoding in the AVID using the Auxiliary Time Code Feature in Media Composer.  In those cases a simpler (non Tri-Level sync) TC source like the SB2 or SB3 will work fine.  Many people use the more expensive Ambient Clockit boxes or Denecke SBT for this function which is total overkill.  These $200 to $300 boxes have the same accurate jam-able TC Generators and will serve to index multiple inexpensive cameras with less than 1 frame accuracy.  (Close enough for lip-sync).  However if you are using Final Cut instead of Avid this method is less useful.  You have to use third party utilities to read the Audio Track Time Code and translate that into XML metadata that FCP can deal with.

------Courtney

[John Steigerwald]

I agree with everything Phillip says, but one possible use where the SB3 is well suited is the situation for cameras that don't accept a continuous time code input and Genlock or where the editor or post stipulates that the cameras must only use REC-RUN time code. (bad idea but old ENG habits are hard to break).  On many of the Pro-Sumer HD video cameras like the Panasonic HVX200 and Sony EX1s  people are putting LTC onto one of the Audio Tracks for decoding in the AVID using the Auxiliary Time Code Feature in Media Composer.  In those cases a simpler (non Tri-Level sync) TC source like the SB2 or SB3 will work fine.  Many people use the more expensive Ambient Clockit boxes or Denecke SBT for this function which is total overkill.  These $200 to $300 boxes have the same accurate jam-able TC Generators and will serve to index multiple inexpensive cameras with less than 1 frame accuracy.  (Close enough for lip-sync).  However if you are using Final Cut instead of Avid this method is less useful.  You have to use third party utilities to read the Audio Track Time Code and translate that into XML metadata that FCP can deal with.

------Courtney

Courtney,

Can you name, or recommend any of those TC utilities for FCP?

[Richard Ragon]

Hows this?

http://www.icehousepro.us/tcode/

http://www.one-n.com/bwftimecoder.html

http://www.videotoolshed.com/?page=products&pID=26

-Richard

[petersont]

Hello Courtney -

In this instance [syncing audio to cameras without dedicated video/tc in abilities, like the HVX 200...) you suggest using the SB3 for generating TC ( jammed from something like the 744t... i assume ) onto a channel of audio...

Is there ever any danger of bleed through? Also, do you ever suggest sending tc via a comtek or Senn G2? Does this work as well?

I ask because arranging for rough location / pilgrimage doc shoot with several different cameras positioned along the way, one pro and others not [Not necessarily all shooting at once] and want as simple a way as possible to give post a fighting chance of easily syncing everything up... so i will record master audio to 744t and jam cameras i can with Sb3 ( as you and other say, tri-level not necessary ) and others either send tc or just use a denecke ts-c slate when possible. I know its all over the place, but my thinking ( right or wrong...) is that between camera mic tracks, Free run time of day on all cameras jammed from 744t , maybe TC on audio tracks, and slate things will come together in post.

I am certainly open to advice and appreciate your time -

thanks,

peterson

[bcopenhagen]

I just did a commercial with the EX-3 cameras.  The production wanted to go "light and quick", y'know, "doc-style" with no slates and no TC references (lockits) on the camera.  They claimed they would only be using the camera mix tracks, and "never, ever sync to my multi-track ISOs" (I was mixing 3-5 people wireless + an occasional boom).  Sounded like a post-production nightmare....

I eventually talked them into jamming the EX-3's to the TC on my 788T.  The cameras WILL jam to an external sync (and indicate they have done so on the onboard monitor) but they WON'T hold it for long on their own.  Any battery-change, menu change, even just a slight breeze will send this camera back to its own internally running TC.  I did everything I could to help out post, re-jamming between rolls, even doing little "bloop" slates, (a quick shot of 1kHz tone onto the camera and the recorder when they were both running).  I haven't had a call from post, so no news is good news, I hope.

Bottom line is, I would recommend definitely setting up a workflow that includes an accurate TC being fed constantly to either the camera's TC input (Lockit or SBT), or sending LTC to an audio track if you can verify that the project will be cut with Avid, and can take advantage of the Aux TC method Avid supports.

Cheers and good luck,

Brian

[RPSharman]

Regarding tri-level sync. 

I have not, nor have I heard of, anyone running anything other than TC from a lock box into a TC input on a camera.  For this function, the SB3 (or the SB2a for that matter) are less expensive and do the job just as well.  Please tell me I'm wrong.  And I am referring to narrative productions and not a concert with fixed camera positions and/or constant recording.

Robert

[Philip Perkins]

Regarding tri-level sync. 

I have not, nor have I heard of, anyone running anything other than TC from a lock box into a TC input on a camera.  For this function, the SB3 (or the SB2a for that matter) are less expensive and do the job just as well.  Please tell me I'm wrong.  And I am referring to narrative productions and not a concert with fixed camera positions and/or constant recording.

Robert

It is generally not a good idea to send ext TC to a camcorder w/o sync that is locked to the edge of the TC frame.  If you do this you are asking the camera to lock to two clocks at the same time, which can result in the infamous "green flash".  This why SBTs and Lockits supply TC and sync both.

Philip Perkins