Does timecode matter?

[Sound Chaser]

When doing location sound for a film does the timecode frame rate matter. I was taught to use 29.97 ND which is the standard for post. All HD cams operate at 23.976 fps. Picture frame rate has nothing to do with timecode between recorder, slate and camera. For consistency I favor 23.976 but, does it matter? With the exception of 29.97 drop which is used in broadcast, and film which must be processed with telecene, wouldn't any timecode work?
I am only asking this because I get the least amount of drift using a solid number like 30fps.

[philper]

Originally Posted by Sound Chaser

When doing location sound for a film does the timecode frame rate matter. I was taught to use 29.97 ND which is the standard for post. All HD cams operate at 23.976 fps. Picture frame rate has nothing to do with timecode between recorder, slate and camera. For consistency I favor 23.976 but, does it matter? With the exception of 29.97 drop which is used in broadcast, and film which must be processed with telecene, wouldn't any timecode work?
I am only asking this because I get the least amount of drift using a solid number like 30fps.

TC is pretty much needed all the time in some form. Even DSLRs record a non-settable form of TC, and once the project is in editorial TC is vital for knowing the project running time, and referring to specific frames. It is also the way multiple devices are synchronized. 29.97 ND is not THE standard for anything, it is common, but (in the USA) so is 23.98. All HD cams DO NOT operate at 23.98 all the time--they can shoot several other rates as well--you ALWAYS have to ask what frame rate they have chosen for each project (esp if you are recording audio on a separate recorder from the camera). Picture TC has lots to do with recorder slate and camera--if by this you mean matching camera frame rate to audio frame rate. Whether the frame rates are identical or compatible re the workflow in use is a choice somebody has to make--and then tell everyone else involved. Not all combos work. There is no reason at all that you should have drift with any TC frame rate if you have picked the correct one for the project work flow and your system is either clocked to the camera or on a recorder with a TXCO-driven ADC.

phil p

[postprosound]

Um, ya! Of course timecode matters!!!!! Isn't that the whole point of sync/timecode to begin with? How are we in post supposed to sync up to what you've worked so hard to record if it's not matched? And yes, I know, slates.... Timecode is faster and works better.
Maybe I don't get your question. Because not having matching fps is like trying to get the left zipper from your jacket and the right from your gym bag to work together.

[apple-q]

Originally Posted by Sound Chaser

When doing location sound for a film does the timecode frame rate matter. I was taught to use 29.97 ND which is the standard for post. All HD cams operate at 23.976 fps. Picture frame rate has nothing to do with timecode between recorder, slate and camera. For consistency I favor 23.976 but, does it matter? With the exception of 29.97 drop which is used in broadcast, and film which must be processed with telecene, wouldn't any timecode work?
I am only asking this because I get the least amount of drift using a solid number like 30fps.

The "least" amount of drift? There shouldn't be any drift if you set everything correctly.

[tourtelot]

NO timecode discrepancy is the only correct way.

D.

[aracu]

Originally Posted by Sound Chaser

When doing location sound for a film does the timecode frame rate matter. I was taught to use 29.97 ND which is the standard for post. All HD cams operate at 23.976 fps. Picture frame rate has nothing to do with timecode between recorder, slate and camera. For consistency I favor 23.976 but, does it matter? With the exception of 29.97 drop which is used in broadcast, and film which must be processed with telecene, wouldn't any timecode work?
I am only asking this because I get the least amount of drift using a solid number like 30fps.

If your question is about configuring the recorder, it does not matter if
you are not actually jamming the recorder to the camera or vice versa.
If you are, then for the timecode to match up in post and be useful the
two machines have to be configured to the exact same frame rate.

[tourtelot]

Even if the recorder and the camera are not jammed, having the same TC rate will allow syncing via TC by establishing one off-set number using a clap or lip sync. Then, assuming TOD (time of day) code, everything else will sync automatically. But why wouldn't you do it correctly and jam the camera (assuming that it is time code capable) to the recorder?

If I (we) are missing some pertinent point about you situation, please tell me (us) more and we can better answer you question.

D.

[aracu]

Originally Posted by tourtelot

Even if the recorder and the camera are not jammed, having the same TC rate will allow syncing via TC by establishing one off-set number using a clap or lip sync. Then, assuming TOD (time of day) code, everything else will sync automatically.
D.

This is better technical advice than what I gave. It allows for more
possibilities and better work habits, even if the people in charge of the
shoot and postproduction are not planning on using time code.

[Jeff Hayat]

Originally Posted by Sound Chaser

When doing location sound for a film does the timecode frame rate matter. I was taught to use 29.97 ND which is the standard for post. All HD cams operate at 23.976 fps. Picture frame rate has nothing to do with timecode between recorder, slate and camera. For consistency I favor 23.976 but, does it matter? With the exception of 29.97 drop which is used in broadcast, and film which must be processed with telecene, wouldn't any timecode work?
I am only asking this because I get the least amount of drift using a solid number like 30fps.

Not sure what you mean by your last statement, or why there would be drift if everything is syncd.

Bear in mind: 29.97 fps TC is 30 fps TC - pulled down, so it is playing 1/10% slower. Quick synopsis: film (yanno, the medium that contains those little holes we call sprockets ) is shot at 24 fps. When the film is xferred to video, the telecine is not playing at true film speed (24fps) - it is playing at 23.976 fps. This is because true color video runs at 29.97 fps, not 30 fps. So the film gets pulled down so that a proper xfer can take place: the first frame of film gets xferred to two vid fields, the next film frame is xferred to three vid fields, the next frame to two, and so on.

If you are shooting on a camera that is already pulled down to vid speed, ie 23.976, ie 29.97, the recorder should also be running at 23.976/29.97.

Hope this helps.

[DannyL]

1) Not only do you want to record the same timecode, you want to reference your wordclock to the video, if applicable.

2) Do whatever Mr Tourtelot says. He has probably forgotten more about recording sound to picture than any of us will ever know, collectively.

Regards;
Danny

[tourtelot]

Nice Danny and thanks, but the cool thing about this is that there is always something new to be learned. That is unless you want to become a crabby old soundman like me

Just built two sets of input cables for the new Arri Alexa camera. Had one in the shop about a week ago and it is by far the most film-camera-like video camera out there. Takes all the Arri prime lenses and all! Fully expect to see a 1000' mag on the back. Built to be one unit, not all kinds of s**t hanging off it like some Canon 5D, put it on your shoulder, put it on the ground and it doesn't fall over! Sweet.

Did find out that there is a time code display bug that Arri is going to fix, so see? All isn't old-hat in the sound for picture world

D.

[Sound Chaser]

Is there any advantage of using the same timecode as the frame rate of the camera. In other words: Can you use 29.97 with a camera who's frame rate is 23.976?

A completely separate issue which may have confused the question:
I am using an Edirol R4 Pro which seems to be drifting @ 23.976

[ebulb]

Could someone explain the need for TC in todays workflow for me ? Im curious to know how it applies because whenever ive needed to do anything i just grab all the video clips and the audio tracks, drag them into vegas and line them up by sight and listening.. then once im happy they look in sync i lock all the audio files and its good to start editing..

Ive had a couple of times where ive mixed fairly contrasting footage also.. A few times ive mixed a red one at 4k, 2 x EX1's in PAL and a Z1 in NTSC and some other POV helmet type camera in NTSC.. i just drag them onto vegas timeline under the 1080 50i template and once ive synced the audio tracks im good to go.. hence im not sure how TC applies under that type of workflow ? I know vegas might not be industry standard but i would have thought FCP or whatever is the norm would be similar ?

[DannyL]

Originally Posted by Sound Chaser

Is there any advantage of using the same timecode as the frame rate of the camera. In other words: Can you use 29.97 with a camera who's frame rate is 23.976?

A completely separate issue which may have confused the question:
I am using an Edirol R4 Pro which seems to be drifting @ 23.976

The Edirol R4 Pro might not support 23.976. You may be able to get this to work by using the digital input: Externally resolve both word clock and SMPTE TC to video (or film rate).Select your sample frequency, closest to the incoming clock, and select external digital input AND external timecode. I do not know if this will fix your issue. The Edirol R4 does not pull down to 23.967 natively, though it may work if bith word clock and time code are locked to the same source.

The problem with using 2 different formats of timecode is resolving them in the end. You either have to resolve the audio to the video or vice versa. There are always problems in the math: 1/29.97 ≠ 1/23.976; You have to multiply or divide by .8 frames to resolve the two time bases (23.976÷29.97=0.8). Since there is no such thing as 8/10 of a frame, eventually you have to drop or add some frames to make the pieces work. In very short pieces, you can sync by ear and eye, which is why I still encourage using a timecode slate with a clapper.

Maybe someone else has a more succinct suggestion with more specific information.....

Regards;
Danny

[LX3]

Originally Posted by ebulb

Could someone explain the need for TC in todays workflow for me ? Im curious to know how it applies because whenever ive needed to do anything i just grab all the video clips and the audio tracks, drag them into vegas and line them up by sight and listening.. then once im happy they look in sync i lock all the audio files and its good to start editing..

Ive had a couple of times where ive mixed fairly contrasting footage also.. A few times ive mixed a red one at 4k, 2 x EX1's in PAL and a Z1 in NTSC and some other POV helmet type camera in NTSC.. i just drag them onto vegas timeline under the 1080 50i template and once ive synced the audio tracks im good to go.. hence im not sure how TC applies under that type of workflow ? I know vegas might not be industry standard but i would have thought FCP or whatever is the norm would be similar ?

Any time you're doing a lot of start-stop recording during the day, having matching timecode on both audio and video is a big timesaver when it comes to matching audio with video. Means anyone can drop into or out of record whenever they need to and it's easy to get it sync'd up again in the edit. If everyone's simply recording an entire show from start to finish and not stopping recording, timecode isn't such a big deal. But if you can easily do it, why not?

(One of the other advantages is that it gives everyone involved a common frame of reference. You can tell someone you thought there was a funny sound at 20:17:42:00 and they can locate to that point as fast as they can type the numbers in. Descriptions like "Just after the start of the second chorus of the seventh song" are a pain to deal with.)

Of course, the vast majority of cheaper cameras have either no or very restricted timecode facilities, so you'll usually have some footage you need to sync completely by eye. But the less of that you have to do the better.

Bearing in mind that not all cameras get their timecode right all of the time, so you often need to double-check sync by eye.

[philper]

Originally Posted by ebulb

Could someone explain the need for TC in todays workflow for me ? Im curious to know how it applies because whenever ive needed to do anything i just grab all the video clips and the audio tracks, drag them into vegas and line them up by sight and listening.. then once im happy they look in sync i lock all the audio files and its good to start editing..

Ive had a couple of times where ive mixed fairly contrasting footage also.. A few times ive mixed a red one at 4k, 2 x EX1's in PAL and a Z1 in NTSC and some other POV helmet type camera in NTSC.. i just drag them onto vegas timeline under the 1080 50i template and once ive synced the audio tracks im good to go.. hence im not sure how TC applies under that type of workflow ? I know vegas might not be industry standard but i would have thought FCP or whatever is the norm would be similar ?

If you are handling everything yourself then you can work how ever you want to. But if you are working with other people, people you might not have ever met, who might be in a different city (or country) and who might be working in facilities that charge your client by the hour, then accurate in-sync TC (with documentation) is pretty much expected. FCP can mix up rates and codecs, but whether or not that is a good idea for the project at hand isn't up to me as a location sound recordist--that gets determined by the producers and the post supe. On my jobs those people tend to care a lot about TC, and have specific instructions about what they want.

phil p

[ebulb]

cool thanks..

[tourtelot]

Originally Posted by ebulb

Could someone explain the need for TC in todays workflow for me ? Im curious to know how it applies because whenever ive needed to do anything i just grab all the video clips and the audio tracks, drag them into vegas and line them up by sight and listening.. then once im happy they look in sync i lock all the audio files and its good to start editing..

Ive had a couple of times where ive mixed fairly contrasting footage also.. A few times ive mixed a red one at 4k, 2 x EX1's in PAL and a Z1 in NTSC and some other POV helmet type camera in NTSC.. i just drag them onto vegas timeline under the 1080 50i template and once ive synced the audio tracks im good to go.. hence im not sure how TC applies under that type of workflow ? I know vegas might not be industry standard but i would have thought FCP or whatever is the norm would be similar ?

That works fine for a few clips. It would be hard, time consuming and expensive to do the same thing on, let's say, House

D.

[mosrite]

The answer to the question is "sometimes."

If you shoot your digital projects like you were shooting on, say, 16mm film (external recorder synced with clapper) then timecode might not be a factor for you at all.

[Sound Chaser]

Originally Posted by DannyL

The Edirol R4 Pro might not support 23.976. You may be able to get this to work by using the digital input: Externally resolve both word clock and SMPTE TC to video (or film rate).Select your sample frequency, closest to the incoming clock, and select external digital input AND external timecode.
Regards;
Danny

Yeah the R4 Pro does support 23.976. It was added as an update 2 years ago. There is just something wrong with the generator. I have searched the blogs and I seem to be the only one complaining about this. Not sure how to go about fixing this problem...otherwise the unit is working out great.
If I link up directly there is no drift...but, no DP will tolerate that! I suppose I could get an additional lockit box and slave the R4.

[philper]

Originally Posted by Sound Chaser

Yeah the R4 Pro does support 23.976. It was added as an update 2 years ago. There is just something wrong with the generator. I have searched the blogs and I seem to be the only one complaining about this. Not sure how to go about fixing this problem...otherwise the unit is working out great.
If I link up directly there is no drift...but, no DP will tolerate that! I suppose I could get an additional lockit box and slave the R4.

Your recorder might be fine, or on spec anyhow. Recorders in the price range of the Edirol do not have very accurate clocks at all, ditto for HDP2, cheaper FW interface boxes etc.. One of the things that causes Sound Devices/Nagra/Zax etc recorders to be expensive is their very accurate (less than a frame per day) clocks. Have you done some tests to see how far off an accurate clock your machine is after an hour? Depending on the sort of shoot you are doing there shouldn't be any trouble from anybody about you hooking up to the TC out of a camera, if that's what you need (and if the camera has a TC out connection). I do this fairly often still, and used to do it on almost every job. You can always send the TC from cam to you on wireless if the cable is a problem.

phil p