View Full Version : Long play


Dennis Cummins
June 17th, 2005, 01:41 AM
hey, anyone know the difference between Long play and just the normal play on panasonic cassettes? I bought some of the metal series 60 minutes cassettes and it says on them ideal for long play which would give me 90 minutes. does long play reduce the quality? Also how do I set my dvx 100 to long play? Is there a switch? Cheers...

Rob Lohman
June 17th, 2005, 03:31 AM
Do NOT use it

That is the advice that most people give. Long play simply has the tape
running slower through the device allowing it to record the same information
to a lower amount of tape.

In theory this should all work fine. However, since the information is more
jammed together (quality should not suffer since it is all digital) if the camera
has a problem READING BACK a certain area MORE informatione will be LOST
(which can results in bad audio or all sort of visual problems).

Tape (and tape mechanisms) is pretty delicate and can easily fail. Since tape
is so very cheap most people just don't think it is worth the risk for 30 minutes
more recording time when they can just pop in a brand new tape.

In the same line of advice most people also say to NOT re-use a tape unless
it is for testing purposes. This for two reasons:

1. it is much more easily to overwrite something by picking the wrong tape (yes, this has happened to people who re-use tapes, no matter how careful they where!)

2. since there is already a signal on the tape it may interfere with the new signal being written down, especially upon reading (yes, this has happened as well)

Therefore most people shoot in SP (versus long play, LP), use a tape only
once and after the footage is on it immediately enable the write protect
slider so you can't accidentally erase it.

Hope this explained it a bit.

Dennis Cummins
June 17th, 2005, 04:47 AM
Cheers Rob that has cleared things up.

has anyone ever experienced aaults by using a tape more than once?? i shoot a lot of footage and regularly use tapes more than once, however your comment below now has me a bit worried...

David Stoneburner
June 17th, 2005, 10:48 AM
Well,
Just like everyone else I can only let you know from experience, which varies between users.

As for LP, I will sometimes use LP when I'm taping something that I know will be over 60 minutes. For some dance recitals and concerts, I have put my GL-1 on a safety wide shot in LP mode and I have also used my TRV-900 for the same thing with no problems. BUT, recently I did a musical that was over an hour and tried using LP mode on my main camera, a DVC-80. For whatever reason I got some artifacting, so the second act I put it back to SP mode. Act 1 was 70 minutes and Act 2 was almost 90 minutes. The LP on my GL-1 was just fine.

As for reusing tapes. I feel safe at reusing a tape around no more than 3 times. Usually the first time I use it for a main camera, and then other 2 times are usually for a back-up camera. I've only have 1 tape give me bad results when I have reused them. Usually after the 2nd or 3rd time, I then use them for personal family video. I always buy the Panasonic professional tapes and only use them. They are the AY-DVM63PQ. They've worked very well for me.

Tim Borek
June 20th, 2005, 01:23 PM
If LP mode performance is such a bad idea, why do camcorder manufacturers even include in models intended for professionals? I can see it being a "value-added" feature for consumer models, but if its use is a faux-pas among professionals, why bother including it as an option?

I've used Panasonic DV cameras exclusively since 2002, and I've never experienced a tape dropout. I've used a DVC80, PV-DV100 (ran all kinds of tapes through this -- TDK, Panny, Sony, and Maxell), and GS120, and record in SP mode 99.9 percent of the time. When shooting LP, however, I've packed the tape (F.FWD to end and then REW to start) each time before shooting; I don't know if this has any effect, but I've heard it's a good preventative measure (for SP too). Because of error risk, I would never reuse a tape recorded in LP, not even for personal use. I still question the gravity of these concerns. Same thing with 80- and 83-minute MiniDV tapes. In the rare instances when a 63-minute tape isn't long enough, I'd rather shoot in LP than spend extra on 80-minute tapes. My experience with LP has been favorable, but I do it only as a last resort; because of the horror stories I hear, I feel like I'm playing Russian Roulette when shooting in LP.

Rob Lohman
June 21st, 2005, 04:18 AM
It is included because it works. However, most professionals just feel the
rewards aren't matched by the possible problems. The risk is just too great.
Why risk it for a couple of bucks? It's just not a good idea.

Now if you have a show that is running for like 80 minutes and you can't
swap tapes then it may be a risk your willing to take. But most professionals
in this situation usually do something of the following:

1. when using multiple camera's they stop one camera recording when it nears the limit before the other one does. Swap taps and continue recording. Then later swap tapes on the other camera. This makes sure you always have continual recording but you will need to cut in edit to another camera (which you may want to do anyway for such a long event)

2. use a direct-to-disk recording device which allows you to record hours at
a time directly to harddisk

Barry Green
June 21st, 2005, 11:04 AM
Or 3, record on an external tape deck that uses large size cassettes.

The DVX offers the ability to trigger an external deck (or camera) when its own tape is nearly empty (called "Chain mode"). If you plugged in a cheap camera or deck in the firewire port and set the DVX to "chain", you could record in full SP quality and then when the tape is about to run out, the DVX will trigger the external camera to start recording automatically, ensuring a lossless transition between the tapes.

Jeremy Davidson
June 21st, 2005, 12:03 PM
I use LP when shooting timelapse footage. I figure it's not a big deal if I get a dropout since I'm throwing out 80%+ of the frames anyway, and its nice to have the extra 30 minutes uninterrupted. I haven't had a dropout yet, but if it does happen I may just shift the closest good frame into its place.

David Stoneburner
June 21st, 2005, 02:47 PM
I just did a shoot this weekend and used my GL-1 for a wideshot backup. I put it in LP mode due to the length of the event. I decided to use, used tape and had one tape that I had used 3 times and one that I had only used once. The one that was used more had a lot of dropouts, the other was fine. I did bulk erase the tapes ahead of time. Again I only use LP for a backup if I have to.

Question:
Barry does the DVC-80 have the same chain feature as the DVX?

Barry Green
June 21st, 2005, 11:37 PM
I believe "chain" is one of the features of the DVX that the DVC doesn't have...

Rob Lohman
June 22nd, 2005, 04:41 AM
David: that's definitely not a good idea as you've found out, LP + reuse of
tapes.

Jeremy: that is an excellent example of where LP would both be useful and
not be a problem if a couple of dropouts would happen. Thanks!

Tom Hardwick
June 22nd, 2005, 06:00 AM
Dennis - there are my thoughts on re-using tapes, and BTW, I earn my living by reusing tape.

I'm of the other persuasion. I reuse my old tapes again and again. Once you know you have a perfect one it's worth reusing indefinately.

We pay 2 quid for something that we hope will be perfect. We get 70 metres
of unspliced amazing multi-layer tape technology, beautifully slit and wound
onto hubs, packed into a tiny matchbox case that has location pins, guide
rollers and tiny bearings. It comes with a spring loaded double-action door, and has a small release lever. It has a clear window bonded into the case, a sliding safety door and is colour printed. It's all machine assembled and packaged in another box complete with self adhesive stickers and a card insert. Two quid! A lot less than a dull sandwich.

If we assume the production process is 99.99% perfect (highly unlikely, and
almost impossible to achieve) then a goodly number of tapes (maybe 100 a
day) will be faulty in some way. Then let's assume the end of line checkers
pick up 99% of these (again unlikely with the vast numbers of tapes being
produced). That still means every year hundreds of faulty tapes hit the
shop shelves and meet the insides of your camcorder. Faulty may only mean
the tape is slit over width, but it may also mean faulty components have
been used in the cassette assembly, or components that are maybe all on the plus side outside production tolerances.

At 2 quid a pop we're asking a lot and expecting too much if we think they'll all be perfect. For important work I use a tape I've tested out 100%, in the same way as I'll use a tripod and camera I've tested out 100%.

tom.