Long Play DV Tapes

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You should try to get the camcorder that recorded the tapes.
You could either try to capture from that unit directly, or make FW copies to another DV unit recording at DV SP speed.

LP mode will not usually play on a unit that did not record the tapes (and sometimes not even on THAT unit.)

[Deditster]

Tapes that are shot in lp mode become prosumer instead of staying professional. The tape gets stretched and therfore you have a tape that is more prone to dropoouts. Professional deck usually won’t play then.

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[deditster] “The tape gets stretched and therfore you have a tape that is more prone to dropoouts. Professional deck usually won’t play then.”

Good sentiment, but a bit inaccurate as to WHY the LP speed is unreliable.
It has nothing to do with a tape being “stretched”.

There’s nothing very special about LP, the camcorder just “slows down the transport” and pulls the tape past the heads at a slower speed.
BUT, the heads are still spinning at the same rate as DV SP, while they attempt to lay down as much digital information as SP. However, the tape is not traveling at a rate high enough to allow “enough space between” the head-swipes (tracks) to make for a reliable recording/playback situation. The tracks on the tape can nearly OVERLAP and cause “confused” playback info.
It therefore REQUIRES that the “tracking” (and head alignment) on the playback unit be EXACTLY the SAME as the record unit so as to be able to track that very small “sweet spot” on the tape.
There is a very good chance that any LP tape will NOT playback on any unit other than the one it was recorded on and, even WITH that unit, it will be 30% more likely that there will be visible dropouts on playback.

If you try to use LP for anything important (I consider any time I go to SHOOT it is important) you stand a very good chance that what you record will be fraught with problems (if it actually PLAYS at all).

The miss-tracking reveals itself in blocky dropouts, image freezes and “no video” (or audio) situations.

Stretched tape or not-stretched tape, just consider LP as unreliable.

[Adam Derstine]

Thanks for the helpful replies. Once again, y’all are the best.

[Paul Dickin]

[Matte] “The tracks on the tape can nearly OVERLAP….”

Hi
That’s how it works in SP mode, the tracks are adjacent (with DVCAM there is a significant gap).
With LP mode the written data tracks overlap, so each edge of the recorded tracks has the previous or next track on the same area of tape.
With a digital recording the replayed digits are either readable or they’re not, so the theory of LP goes that 25% of the track is garbage, then 50% of the track is a good recording, then the other 25% on the other side is garbage again.
But the 2 garbage areas are randomly different, so the 25%+25% of garbage that passes under the read head just doesn’t quite match (by a teensy bit) the 50% of good recording down the centre of the track, and the output of the read head is theoretically a few percent more readable digits than the noise.

Sorry this isn’t a scientifically rigorous (nor precisely accurate) description, but it makes it more clear why SP is not a mode to ever ever use…

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[PaulD] “but it makes it more clear why SP is not a mode to ever ever use…”

Let’s make that “LP”, not “SP” 😉