Who stripes tapes?

[John Sharaf]

You only need to “strip”, meaning record black and time code if you’ll be insert editing onto the tape. Camera masters have traditional been “striped” meaning laying down 30 seconds of bars (thus the word strips) and tone in the analog realm because this helps nominalize the audio and video levels that are subject to adjustment.

In digital there is no such adjustment, but it’s still a good idea to bar and tone in case the master is copied to an analog format and also to bypass the first thirty seconds of the tape to minimize the effect of dirt. In file based digital recording, unless you’re going to transmit the footage over fiber or uplink, where again there might be analog control of audio and video levels, you need not “stripe” (bar and tone).

Hope this helps,

JS

[Jon Agnew]

Thank you, sir. That was all I needed.

[Chris Durham]

I don’t always, but occasionally I stripe tapes to avoid timecode breaks starting the code over. If you’re not careful on some cameras, if you eject a tape, or even review footage from the camera, and switch back to recording on the same tape, timecode will jump back to 0. Striping can prevent this.

If you asked me to explain why I really couldn’t, but I’ve done it before. Might just be an issue in prosumer cameras, or really with mine.

[Richard Herd]

For DV, packing the tape seems more important than striping it.

[Mark Suszko]

I’m with Richard. My experience with all tape is that it actually improves a bit if it’s been run thru a pass or two; the guides and rollers of the deck burnish off additional bits of manufacturing debris, so I feel a “2-pass” tape is actually in its prime. “Packing” a tape by running fast forward to the end and back, makes sure it is free of binding, and only takes a minute or two.

As far as striping digital tape, I would throw down bars and tone on the first minute to use as leader and alignment, and to give a deck enough pre-read time to lock in when exporting something from your NLE timeline.

While we’re on the subject…

Multiple tests have proven (to me anyway) that you can’t effectively use traditional bulk erasers on DV25 tape. In fact, the only effective way we can “erase” such tapes at my office is to record black, bars, or another program over them. When we try to bulk erase them like analog tapes, not only do they not erase completely, they never play or record right in the decks or cameras again, they are effectively ruined. I believe this has to do with the retentivity and coercivity characteristics of the tape stock. To zap it sufficiently to erase program material literally deranges the magnetic material into such a state that the play and record heads can’t overcome it anymore.

But you can prove it to yourself. Take a DVCpro25 tape, record test footage, bulk erase it, try to record new stuff on it, see how stable a playback you can get out of it. Our results were consistently bad over some five tries, unusable for broadcast.
I’m not knocking DVCpro25, I love it, just saying you can’t treat it like you did analog when it comes to erasing.

[Steve Wargo]

We used to always strip U-Matic, S-VHS and Beta tapes before using them for an edit master tape. We always ‘packed” U-Matic. That all ended with DV/DVCAM and we never resumed when we went to HDCAM.

Someone told me a few weeks ago that they always strip their dv tape before laying down a master from an NLE. He claimed that it was easier to check for errors if he was looking at bars and tone. Makes sense but I’ve only had one problem with a master recording.

And, I am going to do another test on some demagged cassettes.

Steve Wargo
Tempe, Arizona
It’s a dry heat!

Sony HDCAM F-900 & HDW-2000/1 deck
5 Final Cut (not quite PRO) systems
Sony HVR-M25 HDV deck
2-Sony EX-1 HD .