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-   -   The "Use One Brand!" Controversy (https://www.dvinfo.net/forum/long-black-line/50892-use-one-brand-controversy.html)

Mike Butler December 9th, 2005 10:50 PM

Well, I don't know jack about this, because I have used exactly one brand and model of tape in my XL1, Panasonic, and it is very easy to reorder. Why in the world would I try to paddle upstream when I have a brand and item number that will get me more of the same ol' reliable tape? Hundreds of them in my case.

Doug Boze December 10th, 2005 12:23 AM

I think it's mainly about reducing or minimizing variables in production. Heaven knows I always seem to forget one-little-thing on every shoot, but at least I'm consistent!

David Ennis December 11th, 2005 06:06 AM

Quote:

Originally Posted by Drew Sommers
This has been explained a little bit more scientifically in a lot of previous posts, tho kind of veiled as it lies in common sense :). There are 2 main lubricants used on tape media (from old reel tapes to the new HD dv), one is the more common "wet" lubricant , a liquid which is coated across the element. The other is a "dry" lubricant, a graphite type material. Both do a great job, except when mixed. Mix water and dirt and you get mud :/.
While it is easy to mix brands and not have any problems, if you start mixing wet and dry lubricants, heads can get real dirty, real fast.

Okay, let's be scientific. If it were true that components in the two lubricants react chemically to form a troublesome third compound (already dubious), it would require mixing of the two at some time and place, and time for the reaction. There is great variability in reaction times for various chemicals, and it is not chemically agressive substances that are chosen as lubricants so it would likely have to be a slow reaction. To my way of thinking, a few micrograms of one lubricant left on a camcorder head by one type will be flushed and brushed off in miliseconds by the lubricant and tape motion of the next type.

The main source of goo that can actually stick to heads is degraded binder from the tape. itself. Here's what I consider a scientific article on tape failure: http://www.clir.org/pubs/reports/pub54/2what_wrong.html

Christopher Lefchik December 11th, 2005 08:20 PM

Quote:

Originally Posted by Laurence Kingston
My first DV camera: a Sony TRV-20 is going strong after five or six years of using whatever DV tape is the cheapest. I expect that it will retire from being out of date long before the constant changing of tape types does any damage.

Quote:

Originally Posted by Richard Zlam
I share a dsr20 with my boss and we use a great variety of tapes with no problems.

From what I've heard, if you mix the different lubricants often enough that no one type has enough time to build up on the tape head, you are at much less risk of problems that if you use one type for a long time and then switch to another type.

As for me, I don't know if the advice to use one type of lubricant is actually based on true problems caused by mixing the two types, but I figure it is worth playing it safe, and so stick to one brand of tape. Why ask for trouble? I've got enough of it already. ;-)

Chien Huey February 15th, 2006 09:20 AM

As stated previously, it's about reducing variables. At the very least if you did have to get your heads repaired/professionally cleaned and the tech asks you "did you switch tapes", you honestly say "no, never I used <brand> tape always". And thus eliminates one possible cause for your issues.

Here are my anecdotes for posterity:

This weekend I used an SVA (School of Visual Arts) PD-150 on a shoot. Out of respect for SVA's equipment bought Sony Excellence tapes. Got the camera, Panny MQ stuck in there. Ran a cleaning tape in there before starting. Over 2.5 tapes in DVCAM mode, the camera barked "Cleaning Tape" 13 times. Hours on the heads were about 80. Could have been some other issue, could have been the tape switching, we won't ever know will we. I did look like a wanker always asking to stop to clean.

Couple weeks ago, I shot a corporate video with a VX2000 owned by the corporation. I've worked with them for years. They order Sony Premiums in bulk and that's all they run. The maintenance on the cams is nonexistant - no cleaning tapes, ever. Not one "Cleaning Tape" message across 4 tapes.

I borrow a friend's DVX100 to shoot stuff on occasion. I asked her any particular brand of tape? Nope. Care for the cam? She lost the lens cap because she threw it at her boyfriend's window to signal him. Out of respect I use Panny MQs but I know all sorts of tapes have been in there. No problems despite the mixing.

My point, based on my experience I don't know if mixing is an issue. But as Chris said before, it's about liability. I shoot narrative stuff mainly (so you can always get another take) but if I shot events and owned my equipment I sure as hell would stick to one brand just to be safe. Last thing I want is a bride and groom suing me because I missed a shot and their videographer friend saw me switching tape brands. I'd rather get sued for incompetence than for something as trivial as tapes.

Chris Hurd February 15th, 2006 09:48 AM

Hi Chien, and welcome aboard.

On one hand, I'm a little annoyed with you for dredging up this tired old thread, but on the other hand I agree with your points completely. Thanks for your input!

As I've said before, the official position of DV Info Net recommending against switching tape brands is primarily to protect myself legally. I don't want someone thinking they can hold me responsible for a messed-up shoot because I said it was okay to change tape brands. It's simply safer from a legal standpoint to continue to recommend against switching tape brands, unless somebody can conclusively prove why I shouldn't. It doesn't matter to me if some folks think the "scientific burden of proof" is upon me to prove there's a problem. I'm not concerned with that at all.

What I am concerned with, is that there is substantial anecdotal evidence right here on this forum that it is a problem, and somebody's attorney might get the bright idea to say, "well, you should have warned against that, or at the very least, not condone that practice" of switching tape brands. So here it is. The flip side is that nobody is going to come after me with a lawsuit for recommending *against* tape brand switching. Even in the following situation quoted below:

Quote:

And because you have personally claimed that tape-switching is a real danger, and because you have put the official weight of your *wonderful* world-class board behind that claim, I could just as conceivably come after you with a lawsuit for causing me to miss a vital shoot because of your dubious warning, which I believed.
No chance of liability over that, no question about it. I'm not responsible for your poor planning which resulted in you not having enough blank tape stock of the same brand for your vital shoot. In other words, if you come up short of your preferred brand of tapes, that's a result of your own poor planning and is entirely your own fault, not mine.

It's not about "scientific evidence" at all, although I would welcome a bonafide scientific study. Frankly I don't have the ways and means, nor the desire to undertake one myself, but I would be very interested if somebody else did. The real issue here is liability -- and for that primary reason over everything else, this site officially recommends against the practice of switching tape brands, unless somebody can give me a compelling reason *not* to. Hope this helps,

Glenn Camhi February 15th, 2006 06:40 PM

Quote:

Originally Posted by Chris Hurd
On one hand, I'm a little annoyed with you for dredging up this tired old thread

Hello Chris,

Sorry this topic annoys you, but I don't see why it should. It's perfectly reasonable to discuss, isn't it? Shouldn't unresolved issues that remain of interest to people always be open for conversation? I'd sure hate to always have to worry about posting something interesting on a forum, like Chien did, for fear it might annoy the moderator -- even if you meant that partly in fun.

Anyway, as long as you repeated your liability theory...

1. Obviously you cannot control who sues you for what. Anybody can sue you for anything. The question is whether they can get anywhere with it (as you illustrate in your above post).

2. As I explained previously, you are in no way liable if you honestly state the facts: that on the one hand there is a good deal of anecdotal reporting of tape switching apparently causing damage, and there is a clear working theory for how this may happen, but on the other hand that other anecdotes report no problems, and the working theory is disputed by some -- and therefore, until you learn of a proper scientific study, you cannot form any rational conclusion or offer an official position. You can explicitly state that you are in no way liable for anybody's decisions, and that you may not have the best or latest information, and advise people to do their own research and make their own decisions. If anyone wants to know your personal opinion for the hell of it, they can ask you.

Simple as that. Clear, honest, and legally safe.

If you really want, you can advise people that if the arguments against tape switching which they read on this forum are sufficient for them, and if they see no significant downside to sticking with one tape brand to the exclusion of trying others, then they should probably stick with one brand to feel safe. You can even warn them that clients could potentially attempt to sue videographers whose cameras malfunction after having switching tapes (as Chien points out), but that you have no idea if they'd have a legal leg to stand on and that's a question for attorneys, not you.

I appreciate your situation and concern, but it seems misplaced: the argument for taking an official position for legal purposes does not seem to make legal sense. Again, I say this with tremendous respect and solely with your best interests and those of your board's participants at heart.

For those who make the "what's the harm?" argument (in regard to offering an official position), that's utterly irrelevant, especially in light of the fact that there is no actual benefit. (There may or may not be any harm in people carrying rabbits' feet with them at all times while shooting video, but if there's not, that's still no justification for telling people they should.) Nevertheless, for those who haven't really thought about it or remain curious, various aspects of the potential "harm" have already been discussed above (not limited to the part of a single example quoted in the prior post).

Best,
Glenn

Daniel J. Wojcik February 16th, 2006 08:53 AM

Quote:

Originally Posted by Glenn Camhi
(There may or may not be any harm in people carrying rabbits' feet with them at all times while shooting video, but if there's not, that's still no justification for telling people they should.)

What about switching the rabbit's foot from the left pocket to the right pocket during a shoot? Will it cause bad luck?

Chris Hurd February 16th, 2006 01:06 PM

The official DV Info Net position is to keep the rabbit's foot in your left pocket.

An easy way to remember this is, "right is wrong, left is right."

I will not be held liable for problems incurred via either pocket, however,

Bob Grant February 17th, 2006 08:21 AM

Well firstly as the issue has always been referred to as a problem induced by mixing wet and dry lubricants the the simple act of switching brands is irrelevant unless you do have a problem.
For example switching from Panasonic to Sony stock has no correlation to the issue if they both use dry lubricants. However switching between two Panasonic tape formulations used to cause this precise problem as one used dry and the other wet lubricants and I seem to recall Panasonic advising that you stick to the one formulation.
The issue is further clouded as manufacturers seem not to say what type of lubricant they use and furthermore the theory is that you have to use one type of lubricant for an extended period and then switch to induce the problem.

We hire DV equipment and sell DV stock. We used to sell Panasonic stock and then switched to Sony. That's a lot of head hours of one brand followed by a different brand. No increase in error rates seemed to occur however we did check that both tape formulations used dry lubricants.

None of this can easily be determine scientifically, the key piece of data cannot be determined easily, namely does a tape use dry or wet lubricant. One could build a matrix of data and try to deduce something from that, you'd also need to filter out a lot of noise from random events, and need a very large dataset to get good confidence.

Looking at the advice being offered I see it as:

Try to stick to the one type of tape. Do this by keeping enough stock on hand. Good advice anyway, who wants to run out of tape. At the least it's an inconvenience, at worst you could blow a shoot.

If you must change tape type and you've been using the same one for an extended period clean the heads first. What does this require you to do, have a cleaning tape on hand. You're nuts if you don't anyway so there's no down side to this advice either.

Wrong advice is only bad advice if it has a negative impact. If anyone can see a negative impact from following this unproven bit of advice then and only then need it be called into question. So far at worst it's unproven advice, not bad advice.

If the advice is to only use stock xyz and it's 10 times the price of every other stock, that's advice that deserves serious scrutiny.

I'd add my own unscientific bit of advice. Use Sony stock in Sony gear and Panasonic stock in Panasonic gear. Only because if you have a problem with the gear they can't weazel out of it with some spurious remark about the type of tape you use.

Chris Hurd February 17th, 2006 11:36 AM

Most excellent, Bob, many thanks for your input -- much appreciated!

Glenn Camhi February 19th, 2006 05:30 AM

Bob/Chris: Yeah, the wet/dry theory has been discussed earlier on this thread and elsewhere. That was the "working theory" I referred to. Many experts say the wet/dry theory makes no sense, that wet residue evaporates quickly and nothing else causes a problem. In other words, the working theory is bogus, according to some. The latest report saying as much aired on NPR a few months ago, but I don't recall who the expert was so I realize that's of little value.

People keep bringing up the "what's the negative impact" question without noticing that has already been discussed, but it's understantable, 'tis a long thread. Not worth repeating. Clearly various points that have been brought up will be left unaddressed, but it's not important. It was just an interesting question Fred originally raised, to analyze and understand, and hear different people's takes on.

Chris: thank you for the rabbit's foot advice. I made the switch and that very day sold a project! (Thanks also for the big laugh!)

G

David Ennis February 19th, 2006 07:54 AM

Quote:

Originally Posted by Glenn Camhi
...Many experts say the wet/dry theory makes no sense, that wet residue evaporates quickly and nothing else causes a problem. In other words, the working theory is bogus, according to some. The latest report saying as much aired on NPR a few months ago...

Glenn, thank you for this and your informative and balanced contributions on this subject. I hope that the quoted expert contradiction of the popular underlying cause-effect theory is given due consideration by the people who have been following this thread.

James Emory February 19th, 2006 08:53 AM

Although I totally understand Chris's position of possible liability because you can be hauled into court for anything whether you're guilty or not, I don't think there's a court in existence that would side with anyone making a liability claim based on opinion. If anything it would and should be the manufacturer of the product that should be liable but they are insulated with all kinds of exceptions. And.......good luck suing one of them. They will make you wish you never even thought about the suit.

Chris Hurd February 19th, 2006 09:16 AM

Quote:

Originally Posted by James Emory
I don't think there's a court in existence that would side with anyone making a liability claim based on opinion.

I have no doubt at all that I'd prevail in such a situation, but I don't want to even bother finding out. That's why I'm sticking with the "no switch" advice. For the last time, as far as I'm concerned it is a liability issue and nothing else. If that bugs somebody to the point where they can't handle how unscientific that position is, then my firm advice is to excersize your freedom of speech and go start your own web site / blog / whatever and preach it from your own platform... because this one is spoken for already.


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