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Chet Hardin August 23rd, 2002 06:50 PM

Duplication woes
Howdy all -

I took a 15 minute project, on mini-DV (a PERFECT copy, PERFECT, no glitches, checked it on TWO decks) to a Pro Duplication House and they made me fifty VHS copies.
When I watched them I noticed two different drop outs. Now, I am a reasonable guy and I understand DV will do this BUT I don't like it.
So I took the tapes back and they said they would look into it. And they did and they concluded that to redo them might not turn out any better. Maybe worse. So they will re-do them, they say, for an additional one dollar a piece.
Now, my questions are:

1. Do I just take this on the chin and right it off to the flaky nature of mini-dv?
2. Get annoyed that they aren't willing to try one more time for free?
3. Should I expect 15 perfect, glitch free minutes of vhs?
4. Or do I pay them the more dough and try one more time?

What is a reasonable guy to do?

B. Moore August 23rd, 2002 07:40 PM

I know it will be hard to prove butI'll bet they had dirty heads - somewhere.
If all 50 have the same glitch in the same place it's got to be in the master deck.
If they're in different places, the recording decks must have dirty heads.

I would say if your tape is excellent to perfect, It's got to be something they did and would DEMAND (nicely at first) that they do them over and look at one or two in the spread and see what they look like.( see if the glitch is in the same place or even not at all).I would if not satisfied remind them that a happy customer only tells 1 or 2 of his friends , where an unhappy customer tells 12.

You'll probably see a change in their attitude! After all if someone hires you to do a job, you make sure it turns out right or work on it till it does.
Good Luck

Vic Owen August 23rd, 2002 08:05 PM

Even with clean heads on my DV2000 I sometimes get 1-2 drops in a 63 minute tape. Yours sounds excessive for a 15 minute clip. I'd demand a redo, with no additional charge. Most reputable places are sensitive about their reputations.

Jeff Donald August 23rd, 2002 09:39 PM

Are you claiming the drop outs are on their VHS tapes? Are they (Dupe house) claiming the drop outs are on your master? It would only be the fault of VHS if the drop outs are not on each tape at the same spot. What brand and grade of VHS tape did they use? What brand and grade of mini DV did you use as a master? If the drop out is on the master do you see it when you play it now? If you can see it now it would be pointless to redo the 50 tapes. If you can't see it, look for it on their equipment so you and the dupe house are comfortable that the master is in excellant condition. If the drop outs are caused by their source player, then it would be fair to ask them to redo at no charge. If the master has the glitch it would be hard to prove their equipment did the damage, so you might as well live with what you've got. Redoing it would only increase the chance of their equipment damaging the master further and producing a worse dupe. Your in a no win situation unless you want to produce another perfect master and show it to the dupe house. After you both agree its perfect, pay the $50 and accept what you get within the limits of mini DV and VHS. Good luck.


Chet Hardin August 23rd, 2002 09:48 PM

Lose lose situation
Hey Jeff.
They are claiming that the sheer nature of Mini-DV precludes the ability to always obtain flawless dubs. That is the basis for their thoughts on the matter.
I made it quite clear to them that I have gone back to the master and where the dropouts occur on the dubs they do not occur on the master. There are NO dropouts on the master.
And I pulled three copies and viewed them and they all had the same dropouts in the same exact frames so I am assuming that the dropouts occured on the dv deck end.
I do not know if they went back and looked at my master or not.
If they did I am 99% positive dropouts wouldn't occur in the same places again.
Boy, this is my first attempt at dubbing Mini-DV to VHS professionally...it ain't going as well as I had hoped.


Jeff Donald August 23rd, 2002 11:26 PM

Well, its not brain surgery. Do your self a favor and ask what brand and model tape player they use to source your master. I suspect they are using a fairly low end mini DV deck. If thats the case, doing it over is a roll of the dice. It might be better, it might be worse. Two drop outs in 15 minutes is not terrible. How bad are they? Can you describe how bad the breakup is? How long does it disrupt the image, fraction of a second, half second?


Chet Hardin August 24th, 2002 08:06 AM

Of the two glitches only one is disruptive. It lasts only a fraction of a second. I would guess over three or four frames.
But it occurs in a crucial shot (of course they are all crucial). The framing of the shot and the pacing of the edit just begs the audience to look at the glitch!
What I am trying to find out is if imperfect dupes from Pro Dupe houses is just part of the business of working with a mini-dv master or not.

Jeff Donald August 24th, 2002 08:55 AM

The very nature of mini DV (mini - small size) makes it more prone to drop outs and glitches. I think the tape is 6mm wide (1/4 inch). I almost hate to say this but I've worked on tapes 2 inches wide. The alignment of the material written on the tapes (tracks) is extremely narrow. The track width is only 10 microns. Ten tracks equals one frame of video and 30 (29.97) frames equals one second of video. This does not allow for much margin for error. Errors occur when irregularities occur in the playback. Irregularities like blemishes on the tape surface, misalignment of the tape path in both the record and playback units, just plan errors (mistaking a 1 for a 0). When an error occurs, error correction algorithms (Reed-Solomon Codes) kick in to try to cover the errors. Algorithms aren't perfect and a sustained error causes noticeable image degradation.

Ok, so what does all that mean? Better quality decks do more than just look cool. They are made to tighter tolerances with better components. They can even have additional hardware to minimize drop outs or lessen their severity. A cheap playback deck can even induce the problem by being out of align. If they are using a cheap playback deck doing them over is a crap shoot (might be worse, might be the same, might be better). Pay your $50 bucks to get in the game and do it again. If they have a high end playback deck you probably got as good as you're going to get.


B. Moore August 25th, 2002 09:21 PM

Hi chet,
When I dupe my dv tapes to vhs I never get any glitches, in fact they make the best vhs I'v ever seen.

Here's a possibility, I had brought one of my tapes to the lacal college to deliver it to the guy I shot it for. We put it in a $2000 panasonic mini-dv deck to down load it into the computer. One shot through the machine and I went home with my tape. When I got home I tried to download it to my G-4 , glitches all over the place. ( the night before I looked at the tape through my G-4 - all was ok) That's when I realized the school machine had had many different tapes put through it ( wet lube, Dry Lube) probably hadn't been cleaned and now the tapes were ruined.The school now has a policy that only 1 brand of tape can be used in the school.

I guess the point I'm trying to make is that when you were done editing , etc. all was ok.
2.) They may be using cheaper, thinner bulk tape that they package. If you have a choice, always use tapes that are made by a tape manufacturer, 15 minute, 30 min. etc. If they make their own it's usually thin and inferior.

Just a few thoughts to ponder!


Don Berube August 25th, 2002 10:40 PM

2 or so droputs in 15 minutes on a VHS tape is more or less acceptable in that VHS is prone to dropouts, everyone knows this. However, 2 droputs that occur in the exact same spot on each of your 50 dupes is not acceptable, assuming that you are correct in that your miniDV Master is dropout free.

Does this transfer house have a TBC inline when they make their VHS dubs?

The transfer house that you are dealing with should redo the dupes free of charge.

I would bring your miniDV Master to them and play it back on your camera to show it is droput free. Have them play your miniDV Master in their deck to verify this.

A good transfer house will stand by the quality of their work and not provide you with a lot of dupes where a droput occurs in the exact same spot on all of your dupes - again, assuming that your Master is droput free.

- don

Jeff Donald August 26th, 2002 06:36 AM

Time Base Correctors (TBC) are not needed with digital formats. Analog formats have time base error which needs correcting. You might want to check and see if the duplication house made an analog dupe master, rather than sourcing from your mini DV master.


Chet Hardin August 26th, 2002 08:56 AM

Sales Rep
Hello everyone, thanks for the input.

Today I am talking to the sales rep I am dealing with at the dupe house. I am hoping to talk him into running off another batch for me, for free.

Thanks again, chet.

Peter Wiley August 26th, 2002 09:37 AM

Dropouts in VHS v Dropouts in Digital
I am wondering if digital dropouts can be compared to analog dropouts.

What' happening when one is playing a digital tape is that digital data is being decoded and used to generate analog video and audio signals. The decompressioin/decoding process can, if I recall properly, correct for minor loss of data on the fly -- in fact, decompression is filling in lots of data.

There would have to be a very noticiable data hole on the digital master to result in a noticable dropout. I think the problem would have to be on the analog side of the duplication process and probably is, therefore, the duplicator's problem.

Tape storage of digital data has been used for decades pretty reliably.

It's been awhile since I read about all this, so correct me if I am wrong.

George Goltz August 26th, 2002 10:14 AM

Ive had very bad experiences from 2 different duplicating houses, from bad audio to bad video, remakes were no better and became very frustrated that from a very clean mini dv had to supply inferior looking vhs to my customers.(high school
graduations, fashion shows.)Iam ready to decline this type of work in the future due to the duplication quality of final product, but can anyone suggest a dup house that has a good track record and does good work at an afordable price? \
( I know vhs is much inferior to mini dv, but Ive gotten total garbage back from these people, also wondering "Dont they review their work?)

Doug Thompson August 26th, 2002 10:19 AM


Did you try doing your own dub to VHS to see how it looks? If it comes out clean, take that dub to the duplicating house and show them how it should look. If you can get a clean dub, then they should be able to as well.

We've found that some dupe houses that are new to DV don't understand the format and create problems with their signal processors, etc. Dirty heads can also be a problem (I'm amazed at the condition of equipment in some dupe houses).

We gave up on dupe houses and do our own duplication (a major part of our business is providing news footage and we usually dub our DV footage to ProBeta for stations that insist on that format).


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