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Blackmagic Cinema Camera & TC Issue

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When I wish to use a BMCC for a shoot, I then face problem where the Camera doesnt have TC Input. Is the below mentioned option workable for stable TC.

 

- TC out from BNC TC out of TimeCode Buddy WiFi master to Sound Recorder

- TC over WiFi from TCBuddy to iPhone (using Movie Slate app)

- TC out from iPhone's Headphone jack to Camera's (BMCC) One Audio Channel to record LTC

 

Would this work stably for some hour of shoot before needing re-jamming or syncing back.

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iPhone has not designed for this professional purpose. The price for the Timecode Buddy Mini RX is £495 ex. VAT. Way cheaper from iPhone.

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iPhone has not designed for this professional purpose. The price for the Timecode Buddy Mini RX is £495 ex. VAT. Way cheaper from iPhone.

This is when we already have an iPhone to spare use as a TC Feeder !

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Do you really need to send audio TC to the camera--is that part of the spec for your job?  On the BMCC etc camera jobs I've done (quite a few) we just sent ref-track audio feeds to the cameras (thus autosync via pluraleyes etc is possible) and showed it a TC slate.  If you are determined to get audio TC into the camera (like for a Resolve etc autosync) then one of the Mozegear TIG boxes might be your friend (combines audio and TC into one connector).   I think what you propose might work but it will be a fragile and fiddly system, not a good recipe where sync concerned.  If you have no extra gear, can you hardwire an audio TC feed from recorder to the camera audio input?

 

philp

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I checked details on Mozegear TIG boxes, they provide Stereo output (One Audio & One TC). I ask : Do one or How do one unmix the track for Mono Inputs on BMC camera ?

 

Secondly is it intended to work like this :

 

Mozegear TIG box gets Jam Synced to TC coming from TCBuddy WiFi master

Mozegear TIG box then give just TC Out thru Audio port to camera Audio CH1 & CH2 on camera gets seperate Audio from line or source. 

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soundman: " . Would this work is what I wish to explore here. "

don't explore it here,  explore it with the client: workflow test!

 

are you really a sound person ?

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soundman: " . Would this work is what I wish to explore here. "

don't explore it here,  explore it with the client: workflow test!

 

are you really a sound person ?

 

No I am not much into Sound. I run a rental house with basic knowledge on equipment I keep to rent out. Client is to travel to London after a week & wished to check if such a setup was possible to work with.

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not really a sound man: " wished to check if such a setup was possible to work with. "

and you figured we would tell you, so you could sound smart..?

 

Not really, wanted to learn if a new work around was possible.  

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The Mozegear audio+TC thing is intended for cameras with tip/ring/sleeve single connector audio inputs like DSLRs or the BM "pocket" camera.  For the full size BM 4K  (not the ENG style one) you just need to get whatever you are sending to TRS phone connectors.  The TC from any source goes in one channel, audio into the other.  I still don't like this method very much, it makes playbacks from the camera on location more of a hassle (to get rid of the TC), and TC is pernicious stuff--it can easily leak into the audio.   The TCBud can work as your TC source, or any other jammable TC box with a solid clock.  You could also hardwire TC out from your recorder.   Note in none of these scenarios is the TC aligned with the frames of the video being recorded, or is the camera running in any sort of sync with the incoming TC--it's just recording the TC.  You will have to determine if this approximate sync method will work for your application, ie does it hold acceptable sync for long enough.  A slate or audio/visual start mark for each take is a really good idea.

 

philp

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Philip hit the nail on the head with a lot of his points. I'm going to share a workflow that I've developed based on BlackMagic Design's recommendations, and every client that has come across it has loved it. The gist is that you sent a timecode feed to audio track 1 and a scratch feed to track 2 and then use Davinci Resolve Lite to sync.

 

Gear required:
- Zaxcom IFB Tx

- Zaxcom ERX-TCD (v1 or v2)
 

Steps:
1. Fork each channel from the ERX on to its own 1/4" end. TC should go over left tip and audio over the right.

2. Set output volume to a maximum of 0dB and TC voltage to 0.031.

3. In the camera, set the audio input level to Mic, with the individual inputs to 75% (May be higher or lower depending on the camera but that is what is working for me these days).

 

In post production it is ridiculously simple to make this work. All the client needs to make it work is the free version of Davinci Resolve Lite. Once they have all their footage and audio in the media pool they:
1. Right click on the video files and select "Jam TC from audio track".

2. Right click on the video files and select "Sync Audio from TC".

 

And they're done. It's a very simple, very painless process and it works incredibly well for virtually any camera; DSLRs, Prosumer bodies like the EX1, or even RED cameras if you're up shit creek without a four-pin lemo adapter. 

 

Now, while I think that Mike is being a tremendous asshole in this thread, he is right when he says that your client needs to run tests to make sure that this workflow works for them. Otherwise you're just causing more problems.

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Even though there is a proper way to sync the bmcc with LTC audio you will be better off to just use a smart slate and forget about camera syncing.

For starters, there's no reason you can't do both. Second, this is the best way to maintain sync, period. It saves loads of time in post production and I've never had a problem with it in a year of working with BMD cameras.

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As I said, I don't like the audio LTC on camera audio track approach very much for a lot of reasons (including that a lot of clients believe this constitutes "sync" of some kind) but workflows using it and apps like Resolve are becoming more common, and will be asked for.

 

philp

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When I wish to use a BMCC for a shoot, I then face problem where the Camera doesnt have TC Input. Is the below mentioned option workable for stable TC.

 

The problem with just merely using audible timecode on a sound track is that there is no reference. You need three things for a piece of video to reliably play in sync: 1) good picture, 2) good reference, and 3) good timecode. The video, reference signal (aka genlock), and timecode all have to work together. If you have free-wheeling timecode that has no real reference to the video, it's going to slide a frame every so often, either forward or backwards, because you're depending solely on the accuracy of the clock crystal built in the camera.

 

This is why shooting with non-timecode cameras is a bad idea. And a pox on Blackmagic for making "professional" cameras without built-in timecode. 

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Let's just be clear about one thing……… and it's the most important thing……… any sound recorded on a BMCC will be shit, as it is with all DSLR's etc.

 

With that in mind, you should be recording Double System anyway.

 

With that in mind, all you need is a TimeCode Slate.

 

So really the question is: "Why are you making this so difficult ?"

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