Need Multicam Gen Lock Help at DVinfo.net

Chris Ficek · January 13th, 2010, 06:06 PM

One of the cameras in our four camera mobile production system has gone down. I suspect it is the camera back but not sure, it won't lock up to sync and the vectorscope is going crazy spinning around.

In any event the shoot is tomorrow morning so I need to find a quick workaround and can not find another compatable CCU/multicable/camera in time. My idea is to take one of our DVCPRO cams that does not have genlock capabilities and feed it into a betacam deck I will hook up to the switcher and genlock. Will the output video from the betacam deck lock with the other cameras? The deck has ref video in and out, if I hook the camera and a signal from my blackburst to the deck will it lock?

Stumped but dont wanrt to tear down the deck rack if this wony work.

SUGGESTIONS?

Bill Vincent · January 13th, 2010, 06:19 PM

Chris, I would be concerned about recording one signal while getting a genlock signal from another source, but I really can't say it won't work. The best thing to do is to try it out - make sure the playback on the beta deck looks good when you are locked with the other cameras through the switcher. You're not going to hurt anything by doing it, but again, recording a video signal from one source while genlocking to another (even internal) can be problematic. (The problem might not show up while recording, but when you try to lock everything in playback is where you'd have a problem - so test it out first.)

Marty Welk · January 13th, 2010, 06:35 PM

i dont know for sure, but the betacam used as a loopthrough would have to have a time base corrector built in. as syncing the camera , and syncing up a signal comming from another camera or for playback, would be two different things.
should be able to tell fast enough, by sending a signal through, or doing a playback, then banging the black burst in it and seeing if it glitches a bit when it syncs up.
or if you see TBC settings in a menu , and of course have the TBC on.

other options, use ONE of the cams as the referance, but you probably already knew that.

been a long time since We had to be genlocked, so that is one thing i could think of.

Chris Ficek · January 13th, 2010, 06:36 PM

I'm not actually recording with the betacam deck, just using it as a kind of poor mans TBC. Does this make it sound more feasable?

Chris Ficek · January 13th, 2010, 06:49 PM

Marty,

You said "other options, use ONE of the cams as the referance, but you probably already knew that. "

Nope, didnt know this, could you explain a little more.

Marty Welk · January 13th, 2010, 06:57 PM

your trying to get all the lines of video data to start at exactally the same moment, by feeding in a "video signal" actually a clean blackburst into the genlock input, or sync.
if you feed a non-genlockable cameras signal out as this "video" signal everything locks to, the rest of the cameras can lock to the one video signal, just like it can lock to the blackburst.
as long as the signal stays within specs , it can be locked to just like a blackburst, problems can occur if the signal goes out of range and stuff, so it isnt a perfect method, but it can "work"
this is dependant on how your switcher handles them all being locked, but not TO the switchers own genlock output.

Chris Ficek · January 13th, 2010, 08:33 PM

Thanks!!!!

That is a way cool work around, and my simple brain gets it! Gonna try it first thing in the AM. Since we last chatted I found a tech at the local CBC station that is willing to give me a portable TBC so my troubles are solved, but I'm gonna try your suggestion as it opens up new possibilities for back up cameras. My multicam is getting pretty long in the tooth so failure at an inoportune time is iminent.

January 13th, 2010, 06:06 PM	#1
Chris Ficek Regular Crew Join Date: Feb 2007 Location: Ontario Canada Posts: 113	Need Multicam Gen Lock Help One of the cameras in our four camera mobile production system has gone down. I suspect it is the camera back but not sure, it won't lock up to sync and the vectorscope is going crazy spinning around. In any event the shoot is tomorrow morning so I need to find a quick workaround and can not find another compatable CCU/multicable/camera in time. My idea is to take one of our DVCPRO cams that does not have genlock capabilities and feed it into a betacam deck I will hook up to the switcher and genlock. Will the output video from the betacam deck lock with the other cameras? The deck has ref video in and out, if I hook the camera and a signal from my blackburst to the deck will it lock? Stumped but dont wanrt to tear down the deck rack if this wony work. SUGGESTIONS?

January 13th, 2010, 06:35 PM	#3
Marty Welk Major Player Join Date: Sep 2008 Location: East Bay Cali Posts: 563	i dont know for sure, but the betacam used as a loopthrough would have to have a time base corrector built in. as syncing the camera , and syncing up a signal comming from another camera or for playback, would be two different things. should be able to tell fast enough, by sending a signal through, or doing a playback, then banging the black burst in it and seeing if it glitches a bit when it syncs up. or if you see TBC settings in a menu , and of course have the TBC on. other options, use ONE of the cams as the referance, but you probably already knew that. been a long time since We had to be genlocked, so that is one thing i could think of. __________________ ----------------sig----------------- Re-learning everything all over again, one more time.

January 13th, 2010, 06:57 PM	#6
Marty Welk Major Player Join Date: Sep 2008 Location: East Bay Cali Posts: 563	your trying to get all the lines of video data to start at exactally the same moment, by feeding in a "video signal" actually a clean blackburst into the genlock input, or sync. if you feed a non-genlockable cameras signal out as this "video" signal everything locks to, the rest of the cameras can lock to the one video signal, just like it can lock to the blackburst. as long as the signal stays within specs , it can be locked to just like a blackburst, problems can occur if the signal goes out of range and stuff, so it isnt a perfect method, but it can "work" this is dependant on how your switcher handles them all being locked, but not TO the switchers own genlock output. __________________ ----------------sig----------------- Re-learning everything all over again, one more time.

January 13th, 2010, 06:19 PM	#2
Bill Vincent Major Player Join Date: Aug 2009 Location: Nashville, TN Posts: 253	Chris, I would be concerned about recording one signal while getting a genlock signal from another source, but I really can't say it won't work. The best thing to do is to try it out - make sure the playback on the beta deck looks good when you are locked with the other cameras through the switcher. You're not going to hurt anything by doing it, but again, recording a video signal from one source while genlocking to another (even internal) can be problematic. (The problem might not show up while recording, but when you try to lock everything in playback is where you'd have a problem - so test it out first.)

January 13th, 2010, 06:36 PM	#4
Chris Ficek Regular Crew Join Date: Feb 2007 Location: Ontario Canada Posts: 113	I'm not actually recording with the betacam deck, just using it as a kind of poor mans TBC. Does this make it sound more feasable?

January 13th, 2010, 06:49 PM	#5
Chris Ficek Regular Crew Join Date: Feb 2007 Location: Ontario Canada Posts: 113	Marty, You said "other options, use ONE of the cams as the referance, but you probably already knew that. " Nope, didnt know this, could you explain a little more.

January 13th, 2010, 08:33 PM	#7
Chris Ficek Regular Crew Join Date: Feb 2007 Location: Ontario Canada Posts: 113	Thanks!!!! That is a way cool work around, and my simple brain gets it! Gonna try it first thing in the AM. Since we last chatted I found a tech at the local CBC station that is willing to give me a portable TBC so my troubles are solved, but I'm gonna try your suggestion as it opens up new possibilities for back up cameras. My multicam is getting pretty long in the tooth so failure at an inoportune time is iminent.