* * Timecode * *

[Derrick Begin]

I need a lesson... To be learned...

The subject of timecode. I have been editing my short film using Avid Xpress DV. What is timecode used for? I haven't really been using it and I want to know so when there is a need to use it, I can.

Explain it to me like I'm a 4 year old. Give examples please, the more visual explaination the better.

How important is it? Whats the scoop? It confuses me, and I don't like being confused.

I would like to learn it properly so I can use it as a tool to move things along efficiently.

Thanks.

[Josh Bass]

First off, it's the numbers you see when viewing your tape, somewhere on the screen, displayed as hours:minutes:seconds:frames (i.e. 01:07:45:25)

Timcode is information your tape records when you record, so that each frame of tape has a specific address and can be immediately located if need be. When you capture footage, and do a batch capture, the computer uses your timecode to find all the clips. When logging a tape so someone else can edit, you'd use the timecode to mark locations of good takes or whatnot on your tape, so the editor can say, "ah, at 6:53:47:22 is the take of scene 3 where the actor doesn't screw his lines up!"

Timecode is absolute. Put that minidv tape in any machine, go to a certain time, and the same thing will be on that tape no matter what machine you're looking on. This is opposed to control track, which is relative. Know how a VHS tape starts counting when you put it in? Go to the middle of a movie, starting from the beginning. Those little numbers should say something like 45:00 (forty-five minutes) to 1:00:00 (an hour-control track on a VHS won't have frames). Now, take the tape out of the machine and put it back in. Back at 0:00:00!

Avid and several other systems are capable of laying down their own time code. THIS I still have trouble understanding the point of. A guy explained it to me once, and now it's gone again. If that's what you meant, my bad.

[Derrick Begin]

Josh,

Thanks for the explaination. I guess since my correspondance between people has just been myself and I know where everything is. Hacking the clip where I deem fit, without regard for time code. However, when I cut I keep the audio/video together.

I will be putting using the timecode into practice.

Thanks for the information.

Cheers!

Derrick

[Josh Bass]

It's good stuff. If you accidentally delete media from you drive, you can recapture it using the timcode. You just put the tape in and the computer will know exactly what to recapture, rather than you having to cue the tape and etc. yourself.

[Alex Taylor]

Also, if you're recording to a 'wild' sound source that supports timecode, you can easily sync up the sound with the footage later.

Unlike a control track, the timecode will be the same throughout the tape regardless of where you start it, but if you shoot a scene then switch to VTR and look at your footage, it will reset to 0:00:00:00 when you start recording again. I think there is a way to get around this on some cams but generally that's the case.

[Robert Knecht Schmidt]

Note that NTSC DV timecode is either drop frame or non drop frame. Drop frame timecode skips 2 frame numbers a minute, 9 minutes out of every 10. Frames themselves aren't skipped, just the numbering of frames, so instead of numbering from 0 to 29 in a second, some seconds are numbered 0 to 28. This reconciles the fact that the frame rate of an NTSC signal is not exactly 30 fps, but rather 30000/1001 fps = 29.97002997 fps, which for convenience's sake people (and the hardware and software systems they design) often round to 29.97 fps. I'm unsure whether drop-frame time code forces the signal to 29.97 fps exactly or alternatively whether it will give a bit of time drift over several hours of video. Also, I'm not quite sure how non drop frame timecode works with an NTSC signal. If anyone can point me to an enlightening resource on either of these issues, I'd be much obliged.

The NTSC Canon XL1 and XL1S use drop frame timecode. PAL users need not worry about this because their system is 25 fps exactly.

[Josh Bass]

Darned if I know. When I was a tape operator at our UPN affiliate, we sometimes received episodes of shows for air that were "non drop frame compatible," and we'd have to copy the tape to another before being able to prep it for air.