GH3 GH3's SMPTE time code support

B

Bruce Watson

Veteran
I've read that the upcoming GH3 supports SMPTE time code. Doesn't look like it generates time code for other devices, but apparently it can read time-code and sync to it if some other device supplies it.

Are there any "reasonably priced" sound recorders that will work with the GH3 to take advantage of this? For that matter, how would one use this to sync a couple of GH3s and a sound recorder?

Just fantasizing before the Holidays...
 
It's of no use whatsoever for synching, as (unless I'm mistaken) there isn't a TC input/output through which the camera could communicate with a separate recorder or another camera. It is there for the same reasons as cameras like the XF100 or EX1 have TC but can't 'communicate' it: so that you can conform your edit sequences with frame accuracy if for some reason you need to return to your original rushes (e.g. you decide half way through your edit that you'd rather be using native AVCHD or a different flavour of ProRes).

Typically, TC and Genlock connectors will add around £1000 to the price of a camera because it is a professional feature for which there is no consumer appetite. Canon, Sony and Panasonic therefore release their cameras in two flavours - a pro (or broadcast) version with TC/Genlock connectors (XF305) and a non-pro (non-broadcast) version without (XF300).
 
Depends on the stability of the internal clock, but you can sync multiple time code referenced devices in post. One just has to determine the correct offset between the individual devices. No different than synching film and audio tape to a slate clapper on a Moviola used to be.
The key to making this work is to make sure all the devices are set to free run and the same TC standard. If you manually start all of the TC clocks at as close to the same time as possible, there won't be much offset to deal with. That way they all maintain a consistent time clock for the duration of the event whether the device is actually recording or not.
Personally I think this is a great feature upgrade for the GH3 and will be useful for multi-cam or multi-timecode device shoots.
I have an 8 channel MOTU firewire digital mixer for my laptop that has full timecode support, so I can do multi-track recording of performance events with the ability to sync to multiple cameras.
 
Razz16mm said:
That way they all maintain a consistent time clock for the duration of the event whether the device is actually recording or not.
Click to expand...

In practice, they will wander in relation to one another and be a few frames out by the time an hour (say) has elapsed - more if they drift in opposite directions, less if they happen to drift together (depends on components, camera temperature, shot content, data rate etc). A video second (e.g. 23.976 frames) on one GH3 will not take the same amount of time as a video second (e.g. 23.976 frames) on a different GH3. If you power down or change batteries, they will end up many seconds out. The timecode will nevertheless be an OKish, rough guide for synching several cameras - an improvement on the GH2's internal clock used in the same way.

The reason for connecting Genlock and TC on cameras that allow you to do so is to force the two cameras to march exactly in step. Without that connection, you can start them marching at roughly the same time (+/- 1 second) but they will not march at the same speed (maybe close enough, depending on your requirements). You'll still be better off synching by audio (e.g. comparison of waveforms or PluralEyes). Of course, frame accuracy is not a requirement of most multicamera shoots and is more of an issue for separate sound, where 2 frames out of sync is very obvious (1 frame you can get away with, even for broadcast!).
 
ABR said:
A video second (e.g. 23.976 frames) on one GH3 will not take the same amount of time as a video second (e.g. 23.976 frames) on a different GH3.
Click to expand...

You've tested this? In ten years of editing DV from several different cameras, I've never once had the clips go out of sync by even as much as a frame over a full hour (wedding ceremony). DV cameras all perfectly sync together, not only acorss models but even across brands. That's the point of having a specific frame rate for video.

It's the damned audio recorders I've had trouble with. They seem to wonder all over the place in their timing. But DV is DV and for me, has always been perfectly in sync. I'd honestly expect to see that with any video recording device
 
TC I think is a huge deal for the GH3. I understand it has a free run so it should make syncing up multiple GH3 posable. I would like to see if they put in any hooks for control via wifi. My tablet wants to know
 
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