Pro Tools HD provides a feature called Satellite Link. This allows up to twelve Pro Tools HD systems to be connected up over ethernet, with all of them running in perfect sync. Functions such as solos, play selections and transport commands are linked, creating an expanded system which will cover the needs of even the biggest projects. (If all 12 systems are HDX 3 systems, you can potentially run up to 9216 voices!)
In this article we're going to look at another feature of Satellite Link, which allows any Pro Tools HD hardware system to be linked up with another Pro Tools machine so the video playback can be run from the second computer, leaving the main machine free to handle just the audio.
In order to use Video Satellite LE, you will need at least one computer running Pro Tools HD with hardware and a second computer to act as the satellite. The good news is, the second machine doesn't have to be running HD software. The standard Pro Tools software includes the functionality required. It's worth noting that in versions prior to Pro Tools 11, Video Satellite LE required a separate ilok licence to work. In Pro Tools 11 and later the feature is included as standard.
Before configuring satellite link, the computers must be connected via ethernet. This can be done either directly or over a local area network. The simplest setup would just be a single ethernet cable between the main computer and the video satellite computer.
Configuring Satellite Link On The Administrator Machine
Whenever you link 2 or more Pro Tools systems together, one machine has to act as the administrator and the others will be designated as satellites. In the case of the basic setup we're looking at here, the main Pro Tools HD system, running on a Mac Pro, will be the administrator and a Macbook Pro will act as a video satellite. After connecting the two machines with ethernet, the next step is to go to the Setup menu on the administrator machine, select Peripherals and click on the Satellites tab. Here, you can give the system a name and designate it as the administrator. In the interface section at the bottom, ensure that you have selected the correct ethernet port.
The next step is to access the Satellites tab on the machine which you intend to use as a satellite, give it a name and check the Enable Satellite Mode box, As you can see from the screen shot above, it's rather more simplistic than on the main machine. This is because I'm using a laptop in this example and so it can only be designated as a satellite. An administrator machine always has to be an HD system with hardware. On the satellite computer, also check that you have the correct ethernet port selected in the Interface section of the Satellites tab. Click OK once configured.
Next, on the administrator machine, click on the System 1 box and assign the administrator (in this case, the Mac Pro) and then click on System 2 and assign the Satellite (the Macbook Pro). Only one computer can act as a video Satellite LE system. The remaining 10 satellites, if used, would have to be Pro Tools HD systems running audio.
Linking and Unlinking Machines In The Transport Window
You will now see a couple of new buttons in the Synchronisation section of the Transport Window
On both the administrator and satellite machines, click the link button. It will highlight in green to indicate that the systems are linked. They will now run in close sync with one another, following the transport and timeline location of the administrator machine.
The satellite system can now run all of the video and the main system can run everything else. Both systems should be running a session with the same start time. In the screen shots below, you can see both sessions. In these examples I still have video tracks on the main system but ultimately these could be removed in favour of running the video externally on the satellite system.
If you need to temporarily unlink a satellite, you can do this from either machine by deselecting its button in the transport window.
Video Satellite LE is a useful way of externalising video playback for post production sessions, leaving the main computer to deal with just audio and easing the load on the GPU. Whilst it is technically possible to run audio from the Video Satellite LE machine, it's probably best avoided as sync is only accurate to roughly +/- half a frame. However, if you have a laptop and a second Pro Tools licence, it can be a good way to free up resources on the administrator system and it provides a separate screen to run full screen video.