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-   -   I hate tape!!! (https://www.dvinfo.net/forum/long-black-line/475686-i-hate-tape.html)

Robert Turchick March 26th, 2010 11:58 PM

I hate tape!!!
 
I'm sitting here with two V1U's transferring tapes for a client. The one tape has dropout and TC problems (tried on both cams) So far the other has been OK but I have 3 more tapes to capture! Which means I'm gonna be up all night!

Last year for the same client I did 23 tapes over a weekend off of XL-1s cams and had problems with those tapes too! Not cheapo tapes either, they bought the good stuff!


Why aren't rental places up to speed with our wonderful Panny 150's, 40's yet?
SO much easier to deal with!

Noa Put March 27th, 2010 03:34 AM

Or you can make a hybrid out of your camera like I did with my Canon xh-a1, after some serious problems with a hdv tape I bought a sony hvr-dr60 and now do simultanious recording to tape and ext harddrive on every shoot, makes me sleep better after a assignment :)

Andrew Smith March 27th, 2010 02:05 PM

Drop a Hard Drive. Now drop a tape.

Tape doesn't lose the data. Tape is better.

Andrew

Robert Turchick March 27th, 2010 02:38 PM

forgot "drop a card"...None of my cams use hard drives!

Card...3x faster than real time to get into my system
Tape...realtime

Card...re-useable
Tape...not without risk of dropout

Card...200 minutes of record time (32gig)
Tape...63 minutes

Card...full 1920x1080
Tape...1440x1080 HDV


hmmmmm...shall I go on?

In any case, I'm venting 'cause at 2am I was still fighting with dropouts and bad streams from the tapes and if they had just hired me to shoot, I would have been asleep by 10pm!

Shaun Roemich March 27th, 2010 03:01 PM

Quote:

Originally Posted by Robert Turchick (Post 1506347)
if they had just hired me to shoot, I would have been asleep by 10pm!

I have had this inner dialog with myself on SO many projects back when I used to freelance edit as well as being full service. It always seemed that people only brought the stuff with issues to me...

Noa Put March 27th, 2010 04:52 PM

Quote:

Originally Posted by Andrew Smith (Post 1506341)
Drop a Hard Drive. Now drop a tape.Tape doesn't lose the data. Tape is better.

Drop a camera, and you can stop shooting with an empty tape as result...

Every medium has it's pro's and con's, mini dv tape does loose data as I have experienced. One full hour full of dropouts on a brand new tape and with a new camera. Even CF tape based recorders can fail, nothing is ever 100% fail safe. If I would drop my harddrive recorder and not my camera, I would still have my footage as I record to 2 different mediums at the same time unless both would fail simultaniously.

Andrew Smith March 27th, 2010 08:37 PM

Having a full hour of dropouts on a new tape is a bit of a concern, and hadn't been my experience.

Ideally, recording to both a drive (or solid state media) and tape at the same time is the best insured workflow.

One day I'll afford one of those fancy hard drive firewire thinggies to add on to my camera.

Andrew

Robert Turchick March 27th, 2010 10:18 PM

This is the scariest part of our industry. And with non-repeatable material, it's even worse. Coming from an audio/music production background, the switch to digital was (and still is) pretty unnerving. And that was almost 20 years ago!
It was YEARS before we trusted Pro Tools enough to do an album project without a backup on tape. And that was only when the drives were redundant and backups were in two other locations after each session.
Losing a musician's "performance of a lifetime" was not an option.

It does scare me relying on cards/hard drives/tape whatever the medium for this type of video taping. Having minimum two cameras is a must. And even with studio style production, we swap cards and backup to two different hard drives between takes.
It's part of the biz we will never get away from!

Jim Andrada March 27th, 2010 10:57 PM

Isn't digitall wonderful?

Zeros and ones. Good or bad. OK or trash. Recorded or clipped. All such nice(?) binary choices!

Having said that, part of the problem with the cheap helical scan drives that are used in DV/HDV cameras is that a lot of the error correcting tricks performed on linear tape (or even high end helical scan tape) are either harder or impossible.

Most people aren't aware that linear tape doesn't write the bits as they are sent to it but instead shuffles them around and reorganizes them in such a way that a "typical" problem like a crimped tape or a scratched tape won't wipe out both the data and the error correcting code that protects the particular "cell" in which that data resides. It is also common to use read heads to read back the just written data and compare it to what was intended to be written. If they don't match the drive stops writing and spaces the tape forward to get clear of the problem area and then reintitiates the write operation without having written the standard end of block info onto the tape. At readback, the drive is smart enough to understand that an incomplete block means that the write was abnormally terminated and it ignores everything until it finds the start of the re-written block. So write errors dont make things stop but do marginally reduce the amount of data that can be written to the tape.

I believe helical scan may try to do some similar things, but I don't think it has the capability to be as thorough as linear tape. I think the larger helical scan formats (1/2 or 3/4 inch tapes) have more such correction capability than the el cheapo drives used in DV/HDV cams , and also have higher budgets for the logic elements necessary to implement a lot of these features such as more onboard memory, more powerful (ie more expensive and more power hungry) processors, etc

Helical scan does have some advantages in so far as the areal density or the number of bits per square inch recorded on the tape. Typcally tape drives will write a wide stripe and read back with a narrower head (known as write wide, read narrow). In the case of helical scan each succeeding write overlaps the previously written data so there is no unused space. There can also be two writers and two readers on the rotating drum set at slightly different angles so that a read head will ignore the overlapping data intended to be read by the next read head. Linear tape has to leave guard bands between the tracks ie unused areas.

At one time the huge Ampex helical scan drives ($250k plus as I recall) that were used for 1 inch wide tape that came in cassettes up to the size of a briefcase actually had the ability to "servo" the read heads (ie, wiggle them at 90 degrees to the data stripe while the drum rotated) in order to better follow the data tracks.

Glenn Davidson March 27th, 2010 11:09 PM

I use a FX1 and and Sony HVR-M15U as a redundant recording device via firewire. I should probably go with the external card recorder. But, I am running FCP 5 Studio and am pretty sure it does not have full support of the card files.

Rick L. Allen March 28th, 2010 07:28 AM

Quote:

Originally Posted by Robert Turchick (Post 1506062)
I'm sitting here with two V1U's transferring tapes for a client. The one tape has dropout and TC problems (tried on both cams) So far the other has been OK but I have 3 more tapes to capture! Which means I'm gonna be up all night!

Sounds like dirty heads and poor maintenance.

Tom Hardwick March 28th, 2010 07:55 AM

Quote:

Originally Posted by Robert Turchick (Post 1506347)
Card...re-useable, Tape...not without risk of dropout!

I'd take issue with that. The simple act of replaying the recorded tape is re-using it, and if it had proved to be an unreliable storage medium we wouldn't have any 70 year old recordings to listen to.

Mini DV tape is so cheap that you're the tester, and the first run through the camera is the most dangerous from a dropout pov, when the high spots are being burnished. I'm much happier using a tape I've tested and found to be perfect.

tom.

Robert Turchick March 28th, 2010 08:39 AM

Quote:

Originally Posted by Rick L. Allen (Post 1506551)
Sounds like dirty heads and poor maintenance.

rentals! and they looked in pretty bad shape. Can't believe the director accepted them!

Glenn Davidson March 28th, 2010 12:40 PM

I have not had good success recycling tape. I use Sony DVCAM 124 and Sony DVC HD 85 and tried using them a second time for backing-up work and found I had more drop-outs. I really need to explore the tapeless work flow.

Robert Turchick March 28th, 2010 12:59 PM

Well as I am transferring the second batch of tapes for this project...made a discovery...one (or both) camera's heads are way out of alignment. Took all 13 tapes and tried them in what I thought was the good camera. ended up with a pile of 6 that wouldn't play (blue screen) but did show picture when fast forwarding during play.
Took those tapes, put them in the other camera and they played fine.
So just for grins, took one of the tapes that did work on the good camera and it wouldn't play on the second.
At least everything will get transferred!


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