GenLock EX3 and EX1: Is It Possible?

In general "Genlock" inputs are designed to accept either full composite video, or just the sync part (without the picture), aka "black burst" or "composite sync". I would be very surprised if you couldn't take the composite video output from the EX1 (via the fiddly miniature connector and adapter cable to RCA) and feed it to the EX3. Or the SDI output from the EX1 and through a converter box to composite to feed the EX3.

All this applies to traditional 29.96FPS NTSC. I don't know that any of the traditional "genlock" behavior works for other framerates, and especially HD???

If you have several sources that you need to feed synchronously into a traditional switcher, you can use the one that does NOT do genlock and use IT as the sync SOURCE to lock all the other sources (and the switcher) TO. I have done this many times with live-switched "image magnification" (just as your orchestra is considering). I have genlock cameras and a genlock switcher, but the laptop computer (which is the source for graphics) does NOT have genlock (none do). So I simply use the laptop computer itself as the genlock SOURCE and sync everything else to it. Works just fine as long as the computer (or whatever source) remains operating and connected :-)

HOWEVER. If you are running SDI into an SDI switcher, then you probably don't need genlocked cameras at all. Since SDI is digital (by definition), the SDI switchers that I have investigated inherently perform the function of "frame buffer" and do NOT require synchronous inputs. For example, the For-A HVS1000HS Hanabi Switcher accepts both SDI and composite (and component) inputs (asynchronously) and switches them all together, even doing various kinds of image manipulation between HD and SD sources, etc. And it is a full-service SEG and DVE processor in the same box. And the Newtek TriCaster.
 
Hi Richard,

I was able to synch off of either output from the EX1, being Component green channel, or the regular composite. I tried both and both seem to provide synch to the EX3, as verified by watching the pedestals on a dual trace scope.

The For-A HVS1000HS Hanabi Switcher is a nice piece of gear. They don't make mention of a full frame TBC function though, so I will have to ask them about whether non synched sources can operate nicely into this switcher. For it's functionality, the price seems reasonable.

We WILL be running SDI, since this would be projected on a screen about 50-70' diagonal in a concert hall and quality will need to be top notch. While SDI is digital, wouldn't there still be some issue about framing? Or perhaps it works just like digital video from multiple cameras on an Adobe Premiere timeline? If the Hanabi switcher can do all that, then this is great news. The only remaining issue is whether HB Communications, the rental outfit that the orchestra uses, carries or can make one available.

PS: Love your tagline about dead air!
 
Along the same lines so......what mixer would you recommend for the EXs.

I had a mixer called the MX1 years ago for composite.

I suppose something like the Video Toaster 5 Live.
 
There is a guy offering a software to drive 2 intensity card and allow to mix picture in full HD.
The software is great and free (for instance).
http://www.vmix.com.au/
A small pc with two Intensity pro should cost a fraction of an HD mixer. (let's say less than $1500 for 2 intensity card+low end core2 duo pc)
You can either feed with HD component or use a HD-DSI converter to hdmi.
(you can find the old HDLink for cheap.)
SDI is great for long distance cabling.

The software is also great if you just need to add logo or people's name over HD video since you can use pictures as input or even AVI movie.
In that case only one intensity card is enough, output can be done on the VGA card directly in DVI to projector for example.
 
nosys70 said:
SDI is great for long distance cabling.
Click to expand...

Thanks for the reference to the switcher application.

So what are people using for long-distance HD-SDI? You can't run cables anywhere near the length of my old SD camera cables (300-600ft) with HD-SDI, even with premium coax. How are people connecting HD-SDI cameras hundreds of feet away? I do mostly location video so I need longer camera runs than typical studio use.
 
well , with good cable (see here http://www.extron.com/company/article.aspx?id=hdsdi_ts ) you should be able to get 100 feet or even 200 feet.
if you need more, well you got a serious problem, and possibly, HD is not viable in such config, or you should go to some ethernet streaming or optical
http://www.evertz.com/products/fiber conversion.
http://www.blackmagic-design.com/products/hdlink/techspecs/
fiber optic is cheap today, but pretty difficult to install (fragile) and you can't cut/solder it like a coax cable
http://anchoroptics.com/catalog/product.cfm?id=354

In that case you better go wireless
 
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The Wiki page that I read on HD-SDI says the distance limit is typically 100 meters.
I think I will need about 100-120' for the concert hall application.
The board member that I am in contact with about this project trial talked about also brining in served content from computer graphics. This would be in the form of paid commercial spots to be shown during intermission and before the concert. But we'll need to make sure we have a 100% reliable switching method. A PC is kinda' shakey.
 
XP is rock solid if you do not have
- your wifi card popping up every 2 minutes
-you antivirus fiddling with every file
-MSN, SKYP, AIM try to connect otr update your contact list every 20 sec.
- google desktop trying to index all your hardisk
- Hp, Adobe, quicktime, itune, google update looking for update every 3 minutes.
-the bluetooth , the webcam , the hotsync, the automatic backup, the nikon usb detector, the power management, the weather info screen saver, all these utilities loaded in memory trying to suck a maximum of your memory.

If you have a plain XP running the minimum processes (15 is ok). there are few chance you get problems.
 
Video capture can be shakey at times, even if you've pruned the process list.

I've shaved mine down from 87 process (at fresh XP install with no apps), to about 31 processes (with everything disabled except the core essentials without which the OS would not boot).

OEM preinstalled Windows is like your example above. My workstations were built from scratch. Only the apps used for editing get installed. Even so, video related stuff can glitch from time to time.
 
xp can run perfectly with 13 process and in the mentionned case, this is no video capture, just converting a signal to another, so it should be pretty smooth.
 
Wow, I haven't found any documentation that says you can run that stripped down. About 28 processes are 'critical system' processes and cannot be shut down. I've studied this issue at length in 2003, when I built my first XP-based editing station. SP2 increased the number of processes even more.
Now, on Windows 2000 Professional, I think I had that stripped down to 15 processes and it worked. But XP, the most I could do was 33. But that's a Premiere editing system with Scenarist on it, so there are some additional processes related to those applications.
 
back to the genlock thing... it seems that only one camera needs genlock in order to be genlocked... do you think it would be the same syncing a canon a1 to a g1?
 
futureman said:
back to the genlock thing... it seems that only one camera needs genlock in order to be genlocked... do you think it would be the same syncing a canon a1 to a g1?
Click to expand...

NO. ALL the cameras must be genlocked if the switcher requires synchronous inputs.

In the special case where you have only two cameras, then you can use the one that doesn't do genlock as a source to lock the other one to. And that assumes that the switcher can itself be genlocked (from the un-genlockable camera).

At the Pacific Northwest Video Show last week I confirmed with the rep that the Four-A Hanabi SDI switcher does, indeed, perform the function of frame-sync inherently as part of the ability to accept SDI inputs. It does NOT require synchronous inputs. Perhaps it doesn't explicitly state that because it is assumed for any SDI switcher.
 
futureman said:
back to the genlock thing... it seems that only one camera needs genlock in order to be genlocked... do you think it would be the same syncing a canon a1 to a g1?
Click to expand...

Just a tech note here, one of the two cameras must have a genlock input. That is a specific requirement, not a video-in input, but a genlock input. I'm not familiar with either of those two Canon cameras, but most consumer cameras (perhaps all) are not equipped with a genlock input.
 
yeah the g1 is the cheapest hd camera that has genlock... i was just wondering if i could get away with a g1 a1 combo to save a few bucks!
 
Then if the A1 has a component video output which you don't need to use for external monitoring then utilizing the green Y connector into the G1 genlock input should work. The only way to truly know is to hook both cameras up to a waveform monitor to check.
 
ZumaDog said:
Then if the A1 has a component video output which you don't need to use for external monitoring then utilizing the green Y connector into the G1 genlock input should work. The only way to truly know is to hook both cameras up to a waveform monitor to check.
Click to expand...

thanks, that is the answer i have been looking for!
 
Using a common sync reference like a slate/clapper, hand clap or a point-and-shoot flash into the lenses really helps a lot to sync the two data streams up in any post environment. I'm assuming of course that there is no facility to jam sync timecode between these cameras.
 
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