Synchronizing multiple camera tracks and audio sources continues to be a popular task with the proliferation of video DSLR devices, since most users are creating multiple files, recording audio off-camera, and syncing everything up in post. Syncing is one of those tasks that haven't disappeared over time; in fact, I think more and more people have to do this now with these new cameras.
PluralEyes can be a useful tool for expediting this process.
Installation and Basic Usage
In Vegas Pro 8 or 9, PluralEyes installs as an extension. The installation is standard fare; accept the license agreement, and it copies files to your hard drive.
The basic usage of PluralEyes is very simple:
• Drag your video and audio tracks to the timeline.
• Select the tracks you want to sync (Ctrl-A for All).
• Choose the PluralEyes extension by clicking Tools > Extensions > PluralEyes (you can also add PluralEyes to the toolbar for easy access).
Choosing the PluralEyes extension brings up a very simple dialog box with three choices: Sync, Cancel, and Change.
Click the Sync button, and the sync process begins. Not knowing how PluralEyes worked, and as someone accustomed to other Vegas scripts and extensions, on my first PluralEyes project, I assumed the process would take just a second or two. On the contrary, the first step took 7 minutes. This project had three camera tracks cut in two places and two additional sources of uninterrupted audio, and it was about an hour in length.
It's important to understand how PluralEyes operates: It creates an audio WAV file as a reference for each track that you ask it to sync (even if your original track is a WAV file). So the time will vary based on four factors: the number of tracks, the length of the projects, the speed of your processor, and the options selected within PluralEyes (discussed later). Fortunately, WAV files typically take the least amount of time to render of any file type.
Once the reference audio files have been created, PluralEyes begins the analysis process. This can take from 1 to several minutes or more depending on all the same factors mentioned previously. On my first project, this step took 4 minutes, for a total of 11 minutes of processing to sync the tracks. I did not have to intervene during any of these steps; it's nice that you can walk away while it does its thing without needing your attention. You can even open another instance of Vegas and work on something else while this is going on.
There are some options you can set if you find PluralEyes is not working in your particular case. In the main dialog box, there is a Change button that lets you set some options for PluralEyes to work with (one of the options is called "Try really hard," which I thought was funny). One option is Level Audio. This was required in one of the projects I tried with PluralEyes because one of the audio sources was recorded a bit soft. The help files for individual options are explained well at Singular Software's website. In addition, Singular Software provides a forum and video tutorials at its website to provide additional support as needed. Using any of these options will add time to the synchronizing process.
A lot of folks have asked about the sync of two or more sources drifting over time on longer projects. On playback the sync starts out fine but gets separated by a frame or two after several minutes. This happens because no device is guaranteed to record at exactly the same clock rate as any other device. The only way to truly, absolutely keep devices in sync is to have a master sync during recording. Most of us don't work on projects with this type of gear, so we compensate in post by splitting and adjusting in the editing software as required. If your clips are not split, PluralEyes addresses this phenomenon during the analysis process by getting its perfect sync near the middle of the project, thus minimizing any drift by having only a little drift at each end of the timeline, instead of everything at the end.
I tested PluralEyes with some complex projects that I thought it might choke on, and it worked fine. In projects where we have used tape, we always capture the tape as one single file, with Scene Detection turned off. It's just the way we work.
In the case of this project, we had one clip where the camera had been started and stopped several times, and the other clip was offline audio that had never been interrupted, PluralEyes would not work. In this case, it moved one event to the end of the other track's event to signal to me that it failed in its attempt to sync. I had one other project file in which PluralEyes would sync some of the tracks but not all of them, and the tracks it failed to sync were moved down the timeline as well. I retried this project using the Level Audio option, and it worked fine. In another instance of failed sync, I recaptured the tape with Scene Detection turned on and five clips were created. PluralEyes synced those clips and the offline audio perfectly.
PluralEyes sells directly from Singular Software for $149 for either Vegas or Final Cut Pro, and there is a 30-day trial offered. It can be installed on two computers and used nonsimultaneously. For Vegas Pro users, the same license is good for both 32-bit and 64-bit Vegas.
Is PluralEyes for you? It depends on your multicam and multi-audio source setup, your level of experience in syncing your sources, and how well your current sync workflow is working for you. For my own professional use, I have mixed feelings about this software. I have a musical and audio background and have been syncing audio tracks in Vegas for many years. Thinking about it linearly, one .veg file at a time, I can do the sync about as well as PluralEyes and maybe just a tad faster depending on the number of clips.
However, I know many users of Vegas and other editing packages who struggle with this step. I'm quite certain there are lots of editors who shudder at the thought of syncing a four-camera shoot with multiple offline audio sources. And there are many more videographers who used to use wireless mics direct to DV or HDV tape who now are recording off-camera audio with HD DSLRs (such as Canon's 5D and 7D and Rebel T2i) and need to sync more sources in their projects.
I do know that if I were recording a 1-hour wedding ceremony with three DSLRs, it could result in approximately 18 clips plus offline audio; rather than devote time to syncing all these sources manually, I would prefer to have PluralEyes work on synchronizing the .veg file for that ceremony while I edited the first dance in another instance of Vegas.
PluralEyes worked perfectly on the four projects I tested it with, though it did take a little bit of time and required some tweaking to get that perfect sync on some of them. If your workflow allows for this, or if you don't want the hassle of synchronizing, I recommend you take the trial of PluralEyes for a test drive. You'll like what you see.
David McKnight (david at mcknightvideo.com) is half of McKnight Video of Houston. He is past VP of the Houston Professional Videographers Association (HPVA), has Sony Vegas Editor certification, is the technical editor of Vegas Pro 9 Editing Workshop (Focal Press), and is a contributor to The FullHD Book (VASST). He and his wife, Christie, are winners of multiple HPVA awards.