Real-world comparison of SP to LP

Shredder wrote on 8/19/2002, 6:46 AM

Hi all,

I'm wondering what your real-world experience with LP mode has been. My technical understanding is:

1. There is NO difference in the data that is written (quality/compression rate)
2. The tape feed speed is slower for LP than SP
3. The track size for LP is 6.7 microns vs. 10 for SP

4. The main theoretical issue that seems to come up is that the data's integrity is at greater risk of drop-outs in LP mode due to the smaller track size.
5. Apparantly LP mode is somewhat non-standard & a tape recorded in one deck in LP is not guaranteed to work in another deck of a different brand/model.

So, what's all of your experience with #4 & #5?

Thanks,

Jon

Comments

salad wrote on 8/19/2002, 7:43 AM

You summed it up perfectly, but didn't we just talk about this recently :-)
Oh, the real world experience?
I have captured DV from friends tapes recorded in LP on a PC-9 using my PC-100, and saw no glitches / drop outs or quality loss (beginning to end). I could not tell the difference. I did however, tell him to please use SP from now on, so as NOT to ever have any prob's. I suppose it would be cool if you could switch back and forth from SP to LP on the same tape.

pat

jetdv wrote on 8/19/2002, 9:55 AM

#5: Slight head misalignments cause greater read errors due to the smaller track size. The heads must be more perfectly aligned for LP. Given similar alignments, all devices that have LP capabilities should be able to read the tapes.

Chienworks wrote on 8/19/2002, 10:43 AM

I've had no problems whatsoever with LP mode, even when switching tapes around between three different cameras (all different brands). Any LP material recorded on any of them was playable on any of them.

pcfx: You can switch from LP to SP and back on the same tape. When playing back, the camera will detect the change and adjust accordingly, although i've seen some cameras need half a second or so to complete the detect/change/resume playback process. Since i doubt any cameras let you change speed while recording, these changes will occur between scenes so this delay shouldn't be a problem.

Shredder wrote on 8/19/2002, 11:07 AM

You can change from SP to LP within a tape, but typically you'l have some visual glitch at the point where the speed changes. In other words, you can't get a clean edit at that point. (But you'd never do that for a final output tape anyway)

Shredder wrote on 8/19/2002, 11:08 AM

So what I hear you saying is that LP is reasonably reliable.

I want to archive some TV shows & it aould be awesome to get an extra 50% out of my tapes. It wouldn't be the end of the world if I had a couple of dropped frames on one of the tapes.

That being said, does anyone adamantly disagree with that?

- Jon

salad wrote on 8/19/2002, 11:52 AM

Thanks. I'll have to make use of that feature someday. Someone told me this can't be done, so I just never tried it, and never came accross it in the manual.
Hmmmmm. Glad this topic came up again.