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post #1 of 10 Old 04-18-2001, 03:17 PM - Thread Starter
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After recording or playing a tape, I always forward to the end before rewinding (in a rewinder of course) to ensure that the tape is packed consistently on the supply reel. I have seen the case where a tape develops bulges in the supply reel when played from & rewound to different spots.

Does anyone else do this? Also, does anyone "pre-tension" tapes? That is, running a full FF then REW cycle before first use. I guess the theory is that by doing this before recording you would avoid any possibility of there being a spot where the tape might stick together or bunch up on the supply reel.

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post #2 of 10 Old 04-18-2001, 05:16 PM
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Not a bad idea. In the post production industry, a master is not even ejected unless rewound. At least it's not supposed to be! The theory is that if the cassette would jam, the damage would be at the head and the first two minutes are not program material.

I would however buy a bidirectional tape rewinder for all of $20 these days. Doing it on the VCR will quickly wear out the parts in the VCR.

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post #3 of 10 Old 04-18-2001, 07:26 PM - Thread Starter
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Definitely use a bi-directional rewinder! I realize on rereading my post that I hadn't made that clear.

BTW - does anyone have one which indicates while powered off which direction of tape travel is selected? Mine uses a push-push toggle with no indication whether it is set for FF or REW until it starts. (And it is invariably the wrong direction! http://www.avsforum.com/ubb/smile.gif)

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post #4 of 10 Old 04-19-2001, 04:18 PM
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Glimmie-

I have never had a problem with ejecting a beta tape in post in the middle but I always roll ahead some bars after the last shoot in my camera before ejecting the tape in the field. The transport on camcorders even on broadcast rigs is not very safe. My betacam editors have no problem in post with gentle ejecting. When it comes to the tapes, I don't mind the loss of an edited master as that doesn't take too long to recover. Loosing a camera original is another story. That would be very costly, disasterous even. I also have had no problem with ejecting a DVCAM tape from a DSR-60 but I have heard some horror stories on the lesser robust DVCAM players and VCR's. Again, in the camera, roll bars well past the last scene and then eject. I think if I had to use the practice of all that FF and RR to the heads and tails everytime I swapped source tapes, I'd need to add significant number of hours to my editing costs.
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post #5 of 10 Old 04-20-2001, 12:06 AM
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After reading here about the dangers of rewinding on our expensive and irreplacable DVHS machines, I picked up an RCA "UVR-2Q" bi-directional rewinder at Fry's for a whopping 14 bucks. I used it for the first time tonight on a just-recorded tape of "Star Trek: Insurrection". Instead of rewinding the tape in the HD1000, I ejected it first and rewound in the rewinder. When I played the tape it began with a few minor video dropouts, and got progressively worse as it played. I stopped and tried it in my DH30000, where it played substantially better, but gradually became unplayable towards the end of the movie.

After much fussing around I finally tried fast forwarding and rewinding the tape several times in the DH30000. That seemed to "fix" the tape. It now plays perfectly on both machines.

Prior to this experience I have had no problems making dropout-free recordings. Now I don't know what to do. I hate to waste precious head-life on rewinder experiments. Has any one here had similar experiences? Are some rewinders better than others?

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post #6 of 10 Old 04-20-2001, 12:27 AM - Thread Starter
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gridleak -

Same rewinder. Also bought at Fry's. Haven't had any problems.


Don -

I realize you were responding to glimmie's comments. I too wouldn't want to have to FF/REW every cassette on every ejection in an edit bay.

In starting this topic, I was really most interested in how people care for their DVHS collections. After recording or playing a movie, the tape is usually relatively near the end. Not too bothersome to FF before rewinding...

Pre-tensioning is another story. I've seen some brands of SVHS blanks where the tape seemed very smoothly wound onto the supply reel. In others, the tension seems very inconsistent.

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post #7 of 10 Old 04-20-2001, 11:45 AM
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Quote:
<font face="Verdana, Arial" size="2">Originally posted by peterd:
gridleak -

Don -

I realize you were responding to glimmie's comments. I too wouldn't want to have to FF/REW every cassette on every ejection in an edit bay.


</font>

Just pointing out how it's done here on the left coast. When a telecine master or prime time show has well over 100 hours of work invested in it, the policy in many facilities is never to eject in the middle. It's just not worth the risk. A re-transfer is possible but time consuming. Remember a maximun 35mm load is 20 minutes. As for assembly, we use servers so there is very little tape shuffling.

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post #8 of 10 Old 04-20-2001, 02:27 PM
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Glimmie-

Yes, I can understand that the siruation is dictated by the work spent on the master. I use a hybrid system here with ABC roll VCR's and a 150G HD server for some stuff. It can online some rather complex stuff with all multilayers coming off the HD that was prebuilt and stored. Once the edl is built, I can generate multiple masters in about 1.5 times real time from the ABC roll system.

peterd-
Experience here on the PVHD1000 is that I don't bother with rewinders. Unlike beta systems VHS does not fully wrap the tape onto the heads for rewind and FF. It is out of the shell on modern machines but does not wear the heads. The real issue is how it wears the transport mechanism. IMO, and experience with consumer machines, we just do not put enough wear and tare on the transport to cause a problem over the short haul. If you were putting about 5 hours a day on this machine then I would give them a life of about 4 years. This has been my experience with consumer machines in a duplication rack. The only part that will need replacing is the pinch roller every year and this is a cheap no brainer replacement costing about $0.65 each in bulk. WE replace our on the dub machines about once every 6 months. Consider it like changing an oil filter in a car. I think they cost $3.00 for a pinch roller assembly that is even easier to replace than the roller itself. More good news on this. These Panasonic consumer VCR's use standard parts and these are easy to find. The other part that seems to go often is the voltage regulator and filters in the power supply. This costs typically about $60 for a complete rebuild power supply. The heads? Well, I have never worn out a consumer head yet but they are rather cheap compared to a professional or broadcast VCR. Like $35 for the part and you'll pay a good $75 for the labor to replace one. I would imagine that the PVHD1000 uses standard head design but I don't know. I did check into the replacement cost on the pinch roller as this will be the first thing to go for me. It cost a couple of bucks and is a standard Panasonic part available as a 3rd party item. There is usually a main drive belt that drives the eject mechanism on some machines. Don't know whether it is gear driven or belt on the PVHD1000 but the belts cost very little, are standard and quick to replace. I replace these with the pinch roller.

I have my PVHD1000 now from new for about 14 months and recorded and played back about 280 2 hour tapes. This is 600 hours. Compared to my duplication VCR's this will give me more life on this HD deck than I'll know what to do with. I'm sure the ozone in the air and the 100 degree heat measured inside the VCR case will do more damage than simple rewinding those tapes. If you are experiencing trouble then you may have something else wrong that external rewinding will not fix. You may have a guide post out of alignment or something came loose in the tape path to cause the uneven rewinding of the tape in the machine. IF the pinch roller is worn or glazed and shiny it will do damasge to your tapes as it creases the tape right after playback or record. Get that changed! The pinch roller rubber will go bad without even using the machine in a few years. Depends on the ozone and other factors how fast it will wear out.

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post #9 of 10 Old 04-20-2001, 06:13 PM
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Back in the old days, I worked for a big a/v tape manufacturer. The technical gurus said the advice for any cassette based format was always to put a new tape thru a full wind/rewind cycle on the machine it would be used in. It tensioned the tape to the machine, which resulted in more reliable record/playback and less stress on the transport mechanism. As far as when to ff/rw after that, it was recommended to store the tape at the leader, at either end, but not in the middle.

The idea was that, when being loaded, cassettes had different amounts of tape tension based on the loading machines and cycling them prevented a bad load from screwing up a VTR. At least that's what they told me.

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post #10 of 10 Old 04-20-2001, 11:01 PM - Thread Starter
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Don -

I too remember consumer decks taking quite a beating from the days when I worked in a dubbing house.

My concern is not so much the gradual wear as the possibility for sudden catastrophe. Putting reasonable extra effort into caring for the tapes is in the hope that they will last longer and that none of them will tempt the deck to eat it! http://www.avsforum.com/ubb/smile.gif

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