GH5 Working with timecode on the GH5

Hey Ironfilm you might know:
I use a tentacle to sync my GH5 with a couple of Lectrosonics PDRs I do this by recording the TC as a sound track and then running it through Tentacle Sync Studio to create synched dailies.
I am now also getting a GH5s which has a TC input. Can I assume that I can feed TC from the Tentacle to the GH5S directly? Will it keep sync I have been hearing conflicting things.


There are various scenarios here, and different ways to do each:

GH5 + MixPre = just loop an HDMI cable from the GH5 to the MixPre

GH5 + Atomos + external sound recorder = use Tentacle Sync E on audio track of both the GH5 and the external sound recorder (unless it is timecode capable)

Another variation:

Panasonic GH5S which has a timecode input + a better sound recorder such a Zoom F8n (easily preferable over any sub $1K MixPre recorder! The F8n is a lot better for a film set) = get a Ultrasync ONE. (just send it into the GH5S with the supplied cable Panasonic gave you)


 
I want the tool that saves me time in edit, to assemble and synchronize in chronological order, video and audio clips originating from multiple cameras and audio recorders. Timecode appears to be the most accessible tool for dslr/mirrorless, but there is more than a bit of folly in the process.

Camera and audio recorders have real time clocks that are pretty good about having minimal drift, but SMPTE timecodes for some reason are not.

The GH5 and GH5s seem ahead of the curve with timecode features but at best, you can jam-synch with the GH5s BNC connector; for the GH5 it's HDMI timecode output only. There is no genlock ability with either, which would synchronize shutters but not always be practical if a tethered device interferes with mobility.

Accordingly, some post edit synch adjustment must be accepted.

An important first step is to synch as closely as possible the current time into all the video and audio devices. For the Panasonic cams, the smartphone image app aligns the timecode between the smartphone, GH5 and GH5s within about 1-2 seconds of each other. For the audio device, you can get it about as close by pressing the 'set' button at the top of the minute. Preferably, the audio recorder timecode can be jam-synched from a connection with a GH5s.

GH5/GH5s HDMI free running output will update the timecode in an audio recorder continuously as long as the two are connected and powered. Seems good because it takes drift out of the equation, but Resolve is only going to look at the starting timecode for insertion into the timeline, so if the HDMI link becomes interrupted after recording begins, it doesn't much matter. As long as the camera was powered and connected when the audio recording started, a camera matching timecode is written into the audio file. Groovy. But in the absence of an HDMI link, the starting timecode for the next audio recording resets to 00:00:00;00. :cry:

On the other hand, an audio recorder jam synched to a GH5s continues to run in the absence of a link which is great, but the starting timecode for any subsequent clips may have drifted if jam-synching with the GH5s isn't repeated periodically.

It's just a reality for me, that BNC or HDMI links between cameras and audio recorders cannot be maintained. One audio recorder connects to the PA system, another to a band or music ensemble, the DJ sound board, the groom's lavalier mic, a backup mic. All the devices are synched to the longest running track. Wireless devices; 2.4 Ghz, UHF/VHF are just not dependable in an environment of RF pollution which most weddings are. And just as I said that, it occurred to me that the bands do seem to have wireless sorted out with their mics, guitars etc., but we've never trusted wireless based on what we aren't in control of from dj's and pa systems which more often than not, almost every time in fact, have dropouts and failures during toasts, speeches, wireless lav mics. For us, we're most secure with wired sound and backup/safety recording tracks.
 
I got a reply from Atomos. Atomos is not actually stripping the HDMI control signals as Atomos devices can be daisy chained but apparently, something is altered that makes audio devices not being able to use triggering.
They offered to file a feature request.
 
I got a reply from Atomos. Atomos is not actually stripping the HDMI control signals as Atomos devices can be daisy chained but apparently, something is altered that makes audio devices not being able to use triggering.
They offered to file a feature request.

I was curious and had been looking into this problem; a google search of 'HDMI timecode' revealed that Atomos created in 2014 an open source HDMI timecode protocol and made it available for free (with registration). Looking at the spec sheet for the Atomos Ninja Inferno and Shogun Inferno was noted HDMI 2.0 input support for Canon, Sony and Atomos Open Standard timecode protocols . No protocol was specified for the HDMI output, leading me to believe it's Atomos own open standard. Speculating of course, but the Sound Design probably supports the Sony, the GH5 is probably using the Sony protocol. My $0.02.
 
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