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Sound Devices 633 Mixer/Recorder Timecode Drift


soundhound82

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For any users of the Sound Devices 633 mixer/recorder or other Sound Devices mixer/recorder, after you have jammed the timecode (to synchronize the camera and mixer/recorder) by connecting the mixer/recorder to your camera via a cable, after the cable is disconnected what rate of timecode drift do you normally observe on the mixer/recorder? How do you deal with the timecode drift over the course of an 8 hour day's shoot for example?

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I use my ERX's as much as possible to avoid this type of situation...SO I can't tell you how much, if any drift is experienced in that regard. When I am unable to have an ERX on the camera, I re-jam as often as I can. Usually at lunch or any kind of location change, battery changes/Power downs. It's probably over kill but I'd rather CYA if they don't want a sync box, and it only takes a second.

You have to really stay on top of the C300's although the MKII is a little better. I've noticed the Sony F7 doesn't hold TC very well either. F5, F55 and most of the ENG type cameras usually do pretty well.

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Yes, it very much depends on the camera. The Alexa for example is pretty good, but they all need a re-jam after a framerate change. So for me it's easiest to keep a TC box on the cam at all times.
The "they don't want a sync box" doesn't happen anymore since I switched to Tentacles. Except maybe when there is a RED involved and they don't have the break out cable for the Sync port

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Good to know your solutions Constantin and mradlauer; I love this forum!

mradlauer, those timecode boxes seem really handy. Are ERX's the main timecode box brand or have you heard of more? Would you know if they work on Blackmagic Design cameras, e.g. the URSA Mini? I know there is a timecode input control on that camera so I assume the box might be able to plug into there.

Also mradlauer, I read that the ERX box is capable of sending a scratch track to the camera, for example when the box is mounted to the camera. This is great because the sound mixer (recordist) who has the soundbag, when he starts recording a take/scene, he can send a scratch track to the camera so its microphone can record that track and hence help greatly to sync audio to video in post very easily! Have you used the ERX's to send scratch tracks to your camera?

 

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TC is used for syncing audio to video. When you have TC you don't need audio anymore. Audio would be for playback only.
The ERX system is great, but you need a transmitter to go with that (at the very least for the audio option), so it's turning into a relatively pricey option.
I'd consider a pure Timecode solution, unless you really relly need audio

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9 minutes ago, Constantin said:

TC is used for syncing audio to video. When you have TC you don't need audio anymore. Audio would be for playback only.
The ERX system is great, but you need a transmitter to go with that (at the very least for the audio option), so it's turning into a relatively pricey option.
I'd consider a pure Timecode solution, unless you really relly need audio

I see what you mean. So you are saying that a timecode box connected to the camera would be okay on its own? And also I guess people who want audio as well (as a backup option) will have to pay more to get the necessary further gear for this?  If this is what you mean then I understand.

This might sound funny but what is the technique used to produce a scratch track? Does the recordist 'scratch' his fingers on the boom mic at the start of recording so it can record a scratch on the camera's audio, which can later help to match with the independent/separate externally recorded audio in post?

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ERX is currently the only way to send audio and TC reference to 1 box on camera. The downside is the TX required to do this is designed to do a lot more than just this therefore making this a very expensive way to go if this is all you want to do with the system. I am sure it's a great option if you are buying into Zaxcom wireless systems in a comprehensive way but otherwise the other options are more economically viable and can offer more features. Eg G3 for audio, Deneke/TCB/ACN/Tentacle for TC.

Despite the cost (c.$2000) I was considering the use of the ZFR300 (recorder) with the ERX as a way of sending audio and TC reference between 2 boxes albeit on 2.4ghz (with a very short range) but this is not recommended. There's a chance someone else will bring a 2.4 ghz system of sharing audio and TC to market in the near future but don't hold your breath.

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58 minutes ago, daniel said:

ERX is currently the only way to send audio and TC reference to 1 box on camera.

...

The Zaxcom RX200 also sends both audio and TC to 1 box on camera.  Of course, this gets into a whole different price range, with two channels of high quality audio, greater distance, and a more expensive system involved.

5 hours ago, soundhound82 said:

...after the cable is disconnected what rate of timecode drift do you normally observe on the mixer/recorder?

...

As to the original question, the Sound Devices 633 typically drifts very little as it contains a premium quality time code circuit.  However, as others have noted, the time code generators on many cameras are not nearly as stable as those on the 633 -- it's important to make that distinction to know where the main issues are. 

Also note that time code does not lock cameras together speed-wise, rather it establishes a common start point on each device and numbers the frames (separately on each device) from there.  To lock devices together, a separate Gen-Lock connection is needed.  For shorter takes Gen-Lock is typically not needed, however, for long takes (like maybe recording a concert), Gen-Lock can maintain a critical lock between devices.  This becomes a much bigger issue when more than one camera is involved. 

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To be honest, I think a little further reading here and elsewhere will help you a lot and you may be able to answer your questions yourself. We can list endless options here, but you won't be able to know why you should pick one over the other. Different jobs have different requirements so a basic understanding is really helpful of what's involved to accomodate the needs of the production company. Once you understand about TC and scratch track and so on, search this forum and read the resultant threads and you will find your answers as these issues have been discussed here several times.

Of course someone can provide all the answers here, but if you don't really understand it, it won't help you

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I decided a long time ago that I wanted to go the zaxcom route to do TC and Scratch. I also have the UHF RX so I have options for doing ENG work or even production work where they want main audio on the camera as well. I wanted to keep my bag rig simple so the ability to use 1 TX for two separate system capabilities has been great. Plus the ERX is super versatile especially when working with DSLR or even with big cameras.

Downside is range...in the bag is not the greatest. I have a directional antenna for the TX when I work on the cart, and it works great.

When I work on my cart, I pull the TX out of my bag and go from there.. I am considering an IFB200 but I can't justify right now, and it's easy to switch back and forth.

Regular sync boxes are on my list as well. There is always a need especially in situations where 2.4ghz is not allowed.

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10 hours ago, soundhound82 said:

For any users of the Sound Devices 633 mixer/recorder or other Sound Devices mixer/recorder, after you have jammed the timecode (to synchronize the camera and mixer/recorder) by connecting the mixer/recorder to your camera via a cable, after the cable is disconnected what rate of timecode drift do you normally observe on the mixer/recorder? 

This is pedantic, but I think worth keeping in mind when talking about this stuff with producers, camera department, etc: 

Sound Devices, Zaxcom, and similar professional location-audio recorders rarely if ever drift. Cameras, however, frequently and quickly drift. It's the camera that gets out of sync.

The suggestions here to build a good basic understanding of timecode and sync issues are good. That will help you figure out what timecode/sync solution(s) will best serve you in a particular situation (both in terms of location and post issues). I just searched for a good basic discussion thread here on JWS...there's lots of good info, but to help you get the most from those discussions, maybe check out some of these tutorial videos from Ambient on timecode, sync, syncing issues with certain notorious cameras (RED, Canon C-300, etc), and related stuff. They only lightly promote Ambient's products (which are really good)...I haven't watched all of these, but those I have are worth the time.

Here's the page with all the videos: http://ambient.de/en/university/

Here's the first video. 5:30min

 

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9 hours ago, Constantin said:

To be honest, I think a little further reading here and elsewhere will help you a lot and you may be able to answer your questions yourself. We can list endless options here, but you won't be able to know why you should pick one over the other. Different jobs have different requirements so a basic understanding is really helpful of what's involved to accomodate the needs of the production company. Once you understand about TC and scratch track and so on, search this forum and read the resultant threads and you will find your answers as these issues have been discussed here several times.

Of course someone can provide all the answers here, but if you don't really understand it, it won't help you

Totally agree with your statement above sir. I was in fact searching for scratch track for filmmaking but got more videos on YouTube regarding scratch track as a DJ technique. Thanks for the tip.

Thanks mradlauer and Jim Feeley for your posts too!

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The bottom line is that you kind of can't count on any camera keeping itself in dead TC sync to a jam from an audio recorder, even if the internal clock of the camera (as in Arri) is excellent: there are too many other factors that can bollux the jam.  In the case of lesser cameras, the clocks are really not reliable for long term sync, so the internally generated TC will drift off the jam pretty fast.  Now that we have PDS (Pretty Darn Small) reliable TC generators avail, I don't see camera dept protestations about added weight etc as being anything other than snootful non-cooperation.  A TIG or Tentacle is basically weightless in the context of even a small camera rig.

 

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18 hours ago, soundhound82 said:

For any users of the Sound Devices 633 mixer/recorder or other Sound Devices mixer/recorder, after you have jammed the timecode (to synchronize the camera and mixer/recorder) by connecting the mixer/recorder to your camera via a cable, after the cable is disconnected what rate of timecode drift do you normally observe on the mixer/recorder? How do you deal with the timecode drift over the course of an 8 hour day's shoot for example?

In the modern production where very often slow motion is required I would leave a jam box on the camera and never just jam.

 

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On 02/08/2016 at 10:50 AM, RadoStefanov said:

In the modern production where very often slow motion is required I would leave a jam box on the camera and never just jam.

 

Good point Rado. The F5/F55 is better than some in keeping sync. The current fashion is to "go off speed" for transitional elements and this throws the F5 timecode out, with reference to the sound recorder. 

I now have a Lockit on the camera as a general bit of kit; it saves on the aggravation to the cameraperson and myself that otherwise is needed with the need to rejam after each trip off sync speed. 

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