Syncing two cameras

[pondball]

Em1.2 with oly 7-14/2.8 (at 10mm) and Em5.2 with Oly 17/1.2
seinhauser lav mic on Em1.2
LumaFusion on IPad

Currently I’m starting both cameras by hand so I knew there would be a sync issue right from the start. Is there some remote or technique that will allow me to start both cameras at the same time?

I am currently using a hand clap to sync but this is only marginally satisfactory as I am out of sync in LumaFusion by a Fraction of a second... but I notice it! Vids are for YouTube and I’m shooting at 30fps to save size of output file.

 

[wjiang]

I don't think there's anything that will be able to guarantee that the propagation delay is the same for both cameras.

Are you manually synchronising? I use Da Vinci Resolve which has an automatic sync feature that does it on the whole recording and seems to work pretty well. The feature is available in the free edition.

 

[DanS]

What you want are time code generators like technical syncs or their competitors.

 

[Robert Davidson]

Identify which camera is out of sync and shift it by 1 or 2 frames either way, then see if sync holds for the full duration. Also check if the onboard sound of the em5 syncs up with the sennhieser.

 

[pondball]

What you want are time code generators like technical syncs or their competitors.

Will both of my cameras record with time codes?
Next step would be to see if the app I’m using will sync with the time codes
That would great if both things were true
Once in LumaFusion I can easily separate the sound track from the video track and then compare the wave forms... it’s just seeing how close I can match the sound waves though. I’ll have to see about the time code options though.

 

[Apollo T.]

Would tethering both to your phone which becomes your remote trigger work?
I only use tethering to get a large view. For me it's like a giant EVF.
I don't know...just a thought.

 

[Robert Davidson]

As I said earlier, Matching the sounds waves and the visual hand clap at frame level is the way to go.

 

[BushmanOrig]

Em1.2 with oly 7-14/2.8 (at 10mm) and Em5.2 with Oly 17/1.2
seinhauser lav mic on Em1.2
LumaFusion on IPad

Currently I’m starting both cameras by hand so I knew there would be a sync issue right from the start. Is there some remote or technique that will allow me to start both cameras at the same time?

I am currently using a hand clap to sync but this is only marginally satisfactory as I am out of sync in LumaFusion by a Fraction of a second... but I notice it! Vids are for YouTube and I’m shooting at 30fps to save size of output file.

My friend unless I misunderstand - the solution is simple...

Start recording on both cameras - stand back and clap your hands... That's your sync signal...

When editing line up to the two timelines with the clap and you in perfect sync...

 

[Robert Davidson]

Will both of my cameras record with time codes?
Next step would be to see if the app I’m using will sync with the time codes
That would great if both things were true
Once in LumaFusion I can easily separate the sound track from the video track and then compare the wave forms... it’s just seeing how close I can match the sound waves though. I’ll have to see about the time code options though.

Both cameras record timecode but that is not the issue, just match the visual clap with the sound wave at frame level then all is done.

 

[Petrochemist]

How close do you need the cameras to sync?
If fractions of a second are significant, then I would use an optical or radio sync, probably via a flash controller.
If you add a programmable delay between the optical trigger & the camera you can correct for repeatable variations in the propagation delay, using manual setting should hopefully eliminate any other variations in delay.

 

[DanS]

Will both of my cameras record with time codes?
Next step would be to see if the app I’m using will sync with the time codes
That would great if both things were true
Once in LumaFusion I can easily separate the sound track from the video track and then compare the wave forms... it’s just seeing how close I can match the sound waves though. I’ll have to see about the time code options though.

Keep in mind this is not a cheap solution, and you will need extra gear. However it is the only the solution that scales well. The clapperboard style of syncing works fine when you have a few clips, but when you start having upper 10's or hundreds of clips it gets real old real fast.

For M43 gear you want LTC (linear timecode) generators. They encode a digital timecode signal as audio. You feed encoded audio into the camera audio, so you will not have actual audio in the video files. Note The latest generation tentacle syncs have a built in mic, but it's for scratch audio purposes only. If your NLE supports it, the encoded audio can be decoded, and used to sync clips.

My set-up is as follows:

• GH5 with Tentacle sync-e
• G7 with Tentacle sync-e
• Zoom F4 for recording external mics (has built in timecode)

Ltc timecode generators are good for keeping consumer grade cameras in sync for up to a few hours of continuous recording, depending on the quality of the individual cameras. 99.99% of people will never need more than this because clips aren't more that a few minutes at a time.

If you needs to regularly shoot clips of a few hours in length you need a camera that has a timecode in port, so the internal clock can be controlled.


If you need to keep stuff in sync for long periods of time (like all day) or need millisecond accurate sync, then you need much higher end gear that supports genlock. Genlock controls the camera at the frame level for lack of a better explanation. It basically tells the camera when to fire the shutter, to ensure extreme sync between multiple devices.

 

[pondball]

My friend unless I misunderstand - the solution is simple...

Start recording on both cameras - stand back and clap your hands... That's your sync signal...

When editing line up to the two timelines with the clap and you in perfect sync...

That’s what I’ve been doing from the start. Very audible hand clap. The Lav is connected to the em1 and is very loud, whereas the em5, not so loud. I still get the wave forms, and maybe it’s the settings in LumaFusion but nudging the tracks To sync perfectly seems to be the issue. I’m very close to a perfect sync... but not there yet.

 

[DanS]

That’s what I’ve been doing from the start. Very audible hand clap. The Lav is connected to the em1 and is very loud, whereas the em5, not so loud. I still get the wave forms, and maybe it’s the settings in LumaFusion but nudging the tracks To sync perfectly seems to be the issue. I’m very close to a perfect sync... but not there yet.

Keep in mind that The only way to get perfect sync, is to use genlock. With timecode (of any type), you can be off by up to 1 frame. Genlock is the only that ensures perfect sync because it controls when the shutters activate.

The most common workaround for this is a transition that's only a few frames in length.

 

[pondball]

For M43 gear you want LTC (linear timecode) generators. They encode a digital timecode signal as audio. You feed encoded audio into the camera audio, so you will not have actual audio in the video files. Note The latest generation tentacle syncs have a built in mic, but it's for scratch audio purposes only. If your NLE supports it, the encoded audio can be decoded, and used to sync clips.

My set-up is as follows:

• GH5 with Tentacle sync-e
• G7 with Tentacle sync-e
• Zoom F4 for recording external mics (has built in timecode)

Thanks DanS
Before the Days of Covid closed everything down here I had been researching external devices and had been going back and forth between Zoom and Tascam... had decided on this one that I could order from a local shop when everything got closed down. https://www.amazon.ca/Tascam-Dr-701...GDK6N8H10K0&psc=1&refRID=934DPA5JVGDK6N8H10K0
A bit of overkill for my needs but I intend to use it for some joint vlogging with another sports addict Once we can safely get together. It has built in time code and would allow me to add a second Lav for my guests while at the same time record some ambient audio from venues

Will have to look up the Tentacle items you referenced as I haven’t come across that before,

 

[pondball]

Just looked up the tentacle devices and found an excellent review from Curtis Judd (one of my favourite video guys)

Will have to view it a few times to fully understand the setup but it’s becoming clearer by the minute! Thanks for the tip!

 

[DanS]

I'd recommend against the 701, its internal clock is known to be subpar, and will drift out of sync, unless you are constantly feeding it with external timecode (requires another Timecode generator). I think Curtis even mentions it in his review of it. In that price range the Zoom F4 is the best option currently on the market. Most cheaper recorders don't support timecode, and the tier above the F4 and 701 is going to put you at at least $1k USD or above till you get all the needed accessories.

Zoom F4 reviews:

Curtis has some good information on his secondary channel you might find useful.

 

[pondball]

Started checking around and it looks like the Zoom f4 has been discontinued... checking out the H6 and H8 and a few others now. Back to the drawing board it seems! ? some of my Vlog shoots will be on location so perhaps having something like the H6 or H8 might work? Dunno. Didn’t read anything about time coding on either unit, but I suppose I could get a less expensive H6 and another Lav to use with the guest... another dunno. Either way, with the coaching vlogs I still plan on using two cameras.

Another option would be to hook a Lav up to each camera and avoid purchasing the Zoom recorders. Sound was pretty good from my current Lav and if I bought an equally as good Lav for the other ... and maybe two of those Tentacle thingies it might make syncing easier. Nothing else to spend the money on these days now that all trips are off for the foreseeable.

 

[DanS]

I haven't heard anything about zoom discontinuing the F4 model, and it would be really odd for them if they did, as they keep models around forever. Maybe they are going to update it to an n model like they did the h4 and f8, or maybe its just out of stock because of covid.

I see Adorama and a few other places have it in stock.

Two other options that are slightly more expensive are the Sound Devices Mixpre 3 II & the Zoom F6. They are both New 32 bit recorders that means you don't have to set/monitor gain. You need to ensure your NLE can handle 32bit though.

$500 USD is roughly the cutoff for recorders with timecode support.


Sound quality wise you can't beat an external recorder (as long as you don't go to cheap), their amps are orders of magnitude better than anything you will find in a camera even a high end studio grade one. You might be ok with a hand held recorder, but it depends on how much gain your mics need. If you need phantom power you are also better off with the larger recorders like the Zoom F or SD Mixpre series, they have better external power options imo.


Also you can't feed an external mic and a tentacle sync into a camera. Well, not unless you are going to getting into the realm of weird/custom adapter cables.

 

[Robert Davidson]

That’s what I’ve been doing from the start. Very audible hand clap. The Lav is connected to the em1 and is very loud, whereas the em5, not so loud. I still get the wave forms, and maybe it’s the settings in LumaFusion but nudging the tracks To sync perfectly seems to be the issue. I’m very close to a perfect sync... but not there yet.

Nudging the tracks to sync perfectly? Are you saying you can't line them up exactly to the frame? Premier Pro allows audio to be shifted by fractions of a frame making this easy. Another option - have you looked at the Olympus sound recorder that starts recording when the camera starts recording? The Olympus LS 100 portable recorder.

 

[pondball]

I haven't heard anything about zoom discontinuing the F4 model, and it would be really odd for them if they did, as they keep models around forever. Maybe they are going to update it to an n model like they did the h4 and f8, or maybe its just out of stock because of covid.

I see Adorama and a few other places have it in stock.

Two other options that are slightly more expensive are the Sound Devices Mixpre 3 II & the Zoom F6. They are both New 32 bit recorders that means you don't have to set/monitor gain. You need to ensure your NLE can handle 32bit though.

$500 USD is roughly the cutoff for recorders with timecode support.


Sound quality wise you can't beat an external recorder (as long as you don't go to cheap), their amps are orders of magnitude better than anything you will find in a camera even a high end studio grade one. You might be ok with a hand held recorder, but it depends on how much gain your mics need. If you need phantom power you are also better off with the larger recorders like the Zoom F or SD Mixpre series, they have better external power options imo.


Also you can't feed an external mic and a tentacle sync into a camera. Well, not unless you are going to getting into the realm of weird/custom adapter cables.

Looks like this definitely calls for more research. Some of those units look very good but size is also an issue with me too. I'd like something portable enough to be able to use it in the field. The 701D was about the limit for max size for me I think. The tough part now is seeing these things in person... notch chance of that during Days of Covid.