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Old December 19th, 2003, 08:39 AM   #16
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<<<-- Originally posted by Norm Couture : Jeff:
When you record in VCR mode without an input signal, you don't get black, you get "No Signal" which triggers the blue screen in playback. It will give you a time code though.
.... -->>>

Isn't that the point? To stripe the tape with timecode?

On the PDX-10, "End Search" only works as long as the tape is left in the camcorder. If you take it out to review other work, or for any other reason, it can't find the end again. Unless you spend the extra money for the tapes with the chip, which I haven't convinced myself to do yet.
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Old December 19th, 2003, 08:47 AM   #17
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According to Daniel Brown of Adobe, if you "stripe" your tape with time code, that time code is retained by the tape perpetually, regardless of tape-overs or gaps between scenes.
When you record on a tape, everything gets recorded over what was previously recorded - including the timecode. Now, since the timecode already exists, it STARTS with that timecode when recording. However, the timecode WILL be replaced with a new timecode. To prove this, take a tape that was recorded in SP and record over it in LP. You will see a timecode jump at the end of the LP section as it goes back to the previous SP timecode.

Unfortunately, this also means that you *could* get a very slight timecode jump IF the tape didn't run at EXACTLY the same speed on the second pass. I would rather see the timecode jump back to zero than try to locate a 2 frame gap in the timecode. Ultimately, I would rather back up the tape slightly into the newly recorded timecode so I get NO gaps (which is what I try to do!).
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Old December 19th, 2003, 08:49 AM   #18
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If I were to leave an accidental gap between 2 shots on my tape, I'd prefer it to be a silent black with video sync rather than an out-of-sync blue screen with white noise in the audio.
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Old December 19th, 2003, 08:54 AM   #19
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Norm,
Yes indeed. I often use the camera to record the occasional sound track, ambience etc on purpose - without shooting video. My point is - it does not matter for the tape, nor for the quality of your subsequent recordings what way you do it. There's no VCR mode on my camera anyway, so I wouldn't know about that. I'd be surprised, though, if VCR timecode is recognised by the DV recording afterwards.
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Old December 19th, 2003, 09:27 AM   #20
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<<<-- Originally posted by Norm Couture : If I were to leave an accidental gap between 2 shots on my tape, I'd prefer it to be a silent black with video sync rather than an out-of-sync blue screen with white noise in the audio. -->>>

Good point. I hadn't actually used the method I described. I have always used the lens cap and not been concerned about the ambient noise. As I finished striping the last tape of a couple of boxes, it occurred to me that I could have done it in VCR mode. I was planning on doing it that way on my next batch, but I think I'll stick to black and the background noise of me clicking away on my keyboard, making posts on obscure bulletin boards. ;^)
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Old December 19th, 2003, 10:46 AM   #21
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Rick,

You say "The reason SMPTE color bars are recorded is to properly set up your waveform/vectorscope levels for digitization regardless of whether your camera is digital or analog." This is not completely true.

It only makes sense to record camera-generated SMPTE (or whatever style) colour bars for an analog camera, or if there is an analog tape or link in the capture chain
This is because a digital camera does not create "red" internally and then record that on tape, complete with camera variations and tape variations that need to be fixed later. A digital camera simply records "255,0,0" which is pure red, regardless of camera variations, tape variations or whatever. This is then captured over 1394 as "255,0,0" - again, no corrections necessary. That is the whole point of digital video technology.

If, on the other hand, there is an analog tape, or an analog link in the capture chain, then there will be a need to have colour bars.

I understand that many individuals and companies still record camera generated colour bars, but this is usually because of an established work process (why fix it if it ain't broke?) or misundersdtanding.

Regards,

Julian
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Old December 19th, 2003, 11:01 AM   #22
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In the PAL system and Japanese NTSC, black level is 0 IRE. No problem. But in North America, NTSC's black level must have a 7.5 IRE setup to play correctly on a TV set.
And to make things more complicated, we use Japanese NTSC DV camcorders which do NOT use the 7.5 setup. They send a 0 IRE signal through their a/v outputs to our monitors and TV sets.
I can see by the pludge section of the color bars at the beginning of a tape whether I'll be watching a correct picture or not. That's one of the reasons I appreciate a recording that starts with SMPTE color bars. Especially when I mix pictures from different sources at editing.
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Old December 19th, 2003, 11:43 AM   #23
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ANALOG WORLD:

If you are talking *analog* editing tape-2-tape it's defintely better to record black (called hard punch - which means just run a signal of black into the record deck) and run it for the length of the tape. Afterwards, rewind and start editing with less caution...control track breaks will occur less this way.

What this allow you to do is "insert" editing as opposed to "assemble". You can assemble if you want to, but if you are a professional and care about your project from start to finish...well, do inserting because its safer. You're less likely to break your control track - which is like the railroad track for the locomotion. If there is one piece of track missing...bye bye locomotion.

If you decide to analog edit using assemble, just beware to always start recording in your last few frames of video. If you don't...it's a lost railroad track and you're bumming.

DIGITAL WORLD:

Blacking a tape isn't really needed. However, you might want make sure that you have timecode being sent to the tape. In the PD150 - you have to actually hit the button for the timecode to head to the tape. I'd definately check your user manual. Just because you have a digital tape doesn't mean its REAL timecode.

Also, in the digital world its still needed for you to backup a second into previously recorded tape. If you don't...it just gets ugly.

Blacking tapes by the bundle used to be common in post houses that edited VHS, 3/4" and Beta etc. In the recent days...I bet that's still common. However, with digital we can have less wear and tear on the heads of our equipment.

Murph
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Old December 19th, 2003, 12:21 PM   #24
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Frank,

My apologies.

I thought you were referring to just striping the first few seconds of a tape, with color bars, as we do, not the whole thing. That's why I was confused as to why audio would be an issue. If you are doing the whole tape, then it would make sense to cancel the audio.

Julian,

We use our SMPTE color bars as a starting reference when digitizing into our AVIDs both from our Mini-DV and BetaCams, with great results. You are absolutely right, it 'aint broke, so we're not fixing it!

Jeff,

I'm no engineer...but my engineer is, and according to the Grand PUBAH, time code in the digital realm is recorded mulitplexed into the video itself and not recorded longitudinally as it would on an analog tape such as from a BetaCam. So, as Edward stated, all previous picture, audio and timecode will be replaced by the new recording.

Anyway, you all have a happy holiday.

RB
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Old December 19th, 2003, 03:43 PM   #25
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I would record room tone in the first 30 or so seconds of your tapes. This way:
1- It gives you filler sound.
2- You give your NLE enough pre-roll to capture your clips. FCP for example defaults to 2 seconds pre-roll.

This has nothing to do with blacking your tapes.
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Old December 19th, 2003, 07:26 PM   #26
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Re: Ditto to Ed's statement.

<<<-- Originally posted by Rick Bravo : snip.

The reason SMPTE color bars are recorded is to properly set up your waveform/vectorscope levels for digitization regardless of whether your camera is digital or analog.

snip

RB -->>>

IF the tape is recorded as a digital signal, like DV and DVCam and their spin-offs, the signal is already digitized. The transfer from tape to computer is just a file transfer. You cannot affect the signal on the way in.

It is useful to use bars for output but then you just as well could generate the bars in your NLE because in both cases, they are computed and are therefore (one hopes), perfect representations. Camera or NLE as a source should not matter.
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Old December 21st, 2003, 09:23 PM   #27
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Always black my tapes. Wasted way too much time with broken timecode in my NLE, having to babysit the capture 'cause I can't to a batch operation.

My camera, a VX2000, will pick up the timecode IF you take the time to find a good place for the procedure; play 'til a few seconds before the end of your existing footage, switch to record mode, and shoot. This becomes a pain when I'm trying to work fast. End Search doesn't work if you take the tape out.

Regarding timecode replacement, if I remember correctly, this has never worked for me. Record a tape, screw up the timecode, go back and record OVER the broken area, and the timecode remains broken.

I think. I could be mistaken, as I've been striping my tapes for a while now.

Mind you, all this is coming from someone who doesn't do too much filming, much less for a living, so extra head wear isn't really an issue for me.
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Old December 21st, 2003, 09:48 PM   #28
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Regarding timecode replacement, if I remember correctly, this has never worked for me. Record a tape, screw up the timecode, go back and record OVER the broken area, and the timecode remains broken.
This is NOT true. The timecode is ALWAYS replaced. However, if you start in a bad timecode it will be replaced with bad timecode. If you back up and start with a good timecode, it will be replaced with good timecode.

The only time a timecode break should be an issue is when you remove the tape. In that case, when you insert the tape, take the couple of seconds necessary to back up into the previous timecode area. AND, before you take the tape out, take 10 seconds to record some expendable footage.
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Old December 21st, 2003, 10:31 PM   #29
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Okay, I think I get it; the stuff is replaced, but it'll still start from zero, wherever you begin re-recording?

That's what fooled me, I imagine--the resulting timecode, while rewritten, was still wrong.

Thanks for the clarification!
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Old December 22nd, 2003, 07:45 AM   #30
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<<The only time a timecode break should be an issue is when you remove the tape.>>

It could also happen if you review shots before the tape is finished. You could accidentally wind or play it past the last timecoded point. Make sure yoy don't.
Some cameras have a end of tape search function for those cases. Use it if you have it.

Otherwise - like Ed said, if you just record - stop - record and so on you should have no problems, and no need for striping. Even if you turn you camera off between takes.
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