View Full Version : Configuring 2 VT3 Systems & Live Swiching...

11-08-2003, 01:37 PM
Does anyone have any info on how I can configure 2 VT3 systems to be able to share the storage drives, so that they can access the same files together...?

Also, because there is so much stuff in this show, I will have 2 editors working on the various b-roll, feature pieces, creating the CG's, and animation on this TV show, that as we use VT3 to switch the show as we lay the show down live to tape, the various feature pieces and b-roll clips already been cut, the director should be able to just fire those clips during the live taping of the show as he also swithes the cameras, inserts CG, etc....right?

Any help would be greatly appreciated...!

BTW - We will be based in Atlanta, Ga if anyone that is very proficient in VT3 applications is looing for a great full-time gig...

Jay Rathman
Exec. Producer

11-10-2003, 09:38 PM
Hi Jay;
In a nutshell, at least the VT machine should have a dual Xeon MB with built in Gibabyte ethernet. The VT machine should have a SCSI RAID for the main video and pre-edited B-roll. The graphic machines should also have gigabit ethernet on each of them. House your DSK graphics on a fast hard drive one of the machines used to generate the graphics and other B roll and then share that drive so that the live switcher and the other graphics machine have access to it. Also, it looks like Fibre channel shared drives on a central server would be a good but pricey option especially if you are creating B-roll live, (replays).

I would go so far as to recommend that at least one of the graphics machines has a VT card in it as well and be used for another DSK layer. This will be very useful when you want to have more live layers. One live DSK layer is not enough. You will have about a 5 frame A/V delay this way, this should be just fine for a live to tape production.

Yes, the director will be able to incorporate all the material, live camera switching, insert CG, animations, and b-roll. Just make sure you are not trying to creating graphics on the live switcher and even though it is possible, don't record to the hard drive, instead record to tape.

Practically, it is a bit confusing in a live show for the switcher to be doing it all; camera switching, DDR loading and playback, CG loading and keying, camera colorist and audio monitoring. VT has all these tools but it sure helps to have two people side by one with the RS-8 hardware switcher and the other with the mouse and keyboard to do the rest. Pre-loading three DDRs with all the material that you can before hand helps a great deal. Two DDR have video clips and the third has your animated keys.

11-11-2003, 11:39 AM
Two completely untested suggestions:

One (easy): You might try networking the machines together (gigabit if you can), sharing drives, and using compressed files such as DV instead of uncompressed RTV. You'll get somewhat lower picture quality than RTV, but since the files are compressed 5:1, it will require 5 times less bandwidth, which may make the difference between this working and not working. If worst comes to worst, you'll need to copy the files to the other machine's local hard drive before you need to go live. You might even be able to set up a script or use a Windows feature to do this in the background.

Two (hard): Back in my Amiga days, I successfully configured two machines to share the same SCSI (1) chain. As I recall I did this by changing the address of one of the controllers (something about drive addresses being 0-7 and the controller normally being 8; changing one controller to 7 let both controllers coexist and access drives 0-6). SCSI-wise this worked great, but the OS wasn't really designed for it (you could obviously corrupt a drive's FS if two machines tried writing to it at the same time). Therefore I was careful to make each drive read-only to one of the two machines, which sometimes took some acrobatics to get a file exactly where you wanted it. But for having fast shared data, it worked extremely well. (None of this would have been easy on any other system; damn I miss the Amiga!) Fast forward to 2003: I have no idea whether the latest SCSI can support more than one controller, or how you would set that up (requires access to low-level parameters), or whether Windows/NTFS could deal with it at all. But I thought I'd throw it out in case anyone else has tried it and can say for sure.

Best of luck getting your setup running! -MG

11-11-2003, 03:54 PM
I have no idea whether the latest SCSI can support more than one controller, or how you would set that up (requires access to low-level parameters), or whether Windows/NTFS could deal with it at all.
That's one of the big advantages with Fibre channel; it supports dual connections.

Dual loops allow Fibre Channel drives to be connected to two separate server environments at the same time. While only one loop can access the drive at any given moment, dual loops allow both servers to share the drive without manually switching. ... This means data used by more than one system can be stored in a central location and accessed by both loop systems. This eliminates the need to duplicate or synchronize data.
A couple other advantages is high speed and long cable runs, (6 miles with fibre optics). The only disadvantage is that FC adds a bit more cost to the system. This however, would be one application that would be well suited to FC.
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