Strange...

I recently made myself the same question, went home and tested my Sony DCR-TRV320 pointed at a clock (good because it has many sharp lines)...
I didn't see any diference between LP and SP.

If you take a look at DCR-TRV620 review at http://www.whatcamcorder.net/reviews/index.html you'll see:

"Performance:
Standard play pictures were of the high standard we have come to expect from Digital8. While there may be a marginal drop in quality from 'straight' digital using DV cassettes, the difference is too small for most eyes to detect. Most interesting was the long play (LP) function, which was more than acceptable. While detail was clearly lost, overall picture quality was still high. The extra running time LP offers makes better value of those 120min Hi8 tapes, giving you around 90min compared to 60min in SP."

Well, for me, not even the rec duration is true since I get 90mn D8 on a 90mn Hi8 tape...

The only real difference is on the audio side (at least for mini-dv). You can't dub audio when you are at LP because it uses 12 bit instead of 16 bit audio (hope I didnt get those numbers backwards...). I use LP mode With my TRV900 mini-dv camera for most all of my video events (weddings, plays, recitals, etc.) because of he extra time I'm given on the tape. I don't dub the audio on the tape so I dont care.

Gang, check your sources again. To my knowledge, jetdv has it right: there is absolutely no difference between SP and LP in terms of data, just a reduction in track pitch (the helical tracks are squished closer together). No difference in audio formats, no difference in image quality. I know nothing about the TRV-900 functions, but I think Sony would be nuts to lock out 16-bit audio at LP speed. My own camera, a Sony TRV-8, behaves identically at the two speeds, and 12-bit/16-bit formats are available for either SP or LP. The only difference is that I get 60 minutes of recording time at SP and 90 minutes at LP. The newer longer tapes offer 80 or 120 minutes.

I also can't comment on D8, but what I have read was that a "120 minute" 8mm tape would run for 60 minutes in D8 mode.

Excuse the thread hijacking, but this little group seems the right ones to ask:

I use Digital 8 tapes. Is there anything good, bad, or ugly about re-using these tapes(ie, taping over footage)? I've certainly not noticed any quality drops or problems with capturing/printing. Elsewhere I was told that since digital information is being recorded, it doesn't matter how many times you tape over. But common sense tells me that there might be problems because tape is a physical, mechanical medium.

?

G

Tape will stretch over time, so excessive recording, playing, rewinding, fast forwarding, etc... will cause quality problems eventually. So, I would say reuse the tape until you start seeing a problem, but do not reuse for things you can't reshoot like weddings, b-day parties, babies first steps, etc...

I typically use Digital8 tapes around 5 times. It really depends on whether or not you want to take a chance with your shots. If you are shooting something you can redo if it doesn't work then you can chance it with the tape. I've found that at around $6 each it's not too much trouble to just dump them after a few uses. I have a teenage friend who lost a whole days shots by reusing an old tape and was not able to recover what he lost. He was pretty sad!

Tom

Just like any magnetic tape (or HD drive!), it will loose some quality with *use* AND with *time*. I don't have reused tapes at service (not yet), but I will. It should also be good policy to backup some important tapes from time to time (5-10 years ??).
I just use LP mode, but I'm aware that the same magnetic material will be less reliable with more bits of information on it... I just hope the reliability stays at a good level.
(BTW, I just buy Hi8 tapes...)

Back to original question, I think LP and SP are just tape velocity dependent. I do believe some funtions are not accurate enough in LP mode (mechanical issues) and some manufactures could not allow them in this mode. My Sony doesn't use LP if tape is a 8mm. LP is reserved to Hi8 and Digital8 tapes (guess why?)

If some footage is VERY VERY important, we should use SP mode to store it (obvious), but you could always shoot it in LP mode, and transfer to SP at home.

My D8 has the same functions in LP and SP as far as I know.
It also has some extra funtions, not implemented by Sony, like DV in, manual White Balance, Zebra effect, manual sound level, time-lapse mode, etc, but that's another story...

jopereira,

>It also has some extra funtions, not implemented by Sony, like DV in, manual White Balance, Zebra effect, manual sound level, time-lapse mode, etc, but that's another story...<

Sounds like an interesting story. Did you hack your camera? Do tell....

G

Jopereira,I'm also interested in hacking my Sony D8 to enable the functions you describe. Do you have a link to the info ? And also, could you give the model number of your camera, and say whether it's NTSC or PAL ? Thanks..

Re: hacking cameras, I read something somewhere that because of strict European import rules about videorecording devices, some Europeans were hacking their Sonys in order to get DV in, I think. If I recall, devices that combine a camera function and the VCR/recording function violate something, so Sony (and others?) actually produce different versions for Europe.

there are switches in the camera firmware that turn options on and off and enable or disable certain functions. you can get "special" remote controls (lanc only I think) that can switch those functions on.

European models just have certain functions turned off, but they are still the same hardware and software that we get in the U.S. so the DV IN and zebra stripes and everything will work on European models if you just turn them on. search the web and you can probably find the remotes.

You are correct. In my checking on the TRV-900, in SP mode you have the ability to select 12 or 16 bit audio. 12 bit gives you the option to add another audio track later. LP mode only gives you the 16 bit option, so, Riredale, you are right.
A clip from a website...
"You can select 16 bit at 48kHz, or 12 bit at 32 kHz audio sampling, but there is little reason to choose 12 bit audio. If you do record audio in 12 bit mode at the SP tape speed, you have the option to dub a second audio track later, after recording the video."

dave

Back to the difference between SP and LP.

When setting up a lab, recently, we were having very occasional, but bad tape portability problems when we moved a Mini-DV tape from the camcorder which recorded it to other camcorders or Mini-DV decks. After consulting with a Sony regional rep (camcorders) and a JVC regional rep (decks and a few camcorders), we were told, by both, on separate occasions, the same thing.

You are MUCH less likely to have compatibillity problems during playback on "Other" camcorders and decks if you use SP on ANYBODY's camcorders. Moving to LP is asking for trouble, according to them, because if you move to another camcorder or deck it is more likely to play badly. The more expensive the equipment, the less likely you are to have problems, mainly because people with very expensive equipment are more likely to have it serviced completely from time to time. But, the possibility doesn't entirely disappear at ANY price level, according to them.

By the way; the thing that made us decide to go with SP was not compatibility right now, it was FUTURE compatibility. If you use LP and play back on the same camcorder, fine. But, one of these days that particular camcoder is going to die. Then, we were going to face BIG problems if we couldn't play things back.

Now, I don't know if all that they told us is true, but we switched completely to SP, and have had almost NO portability problems since.

You could always record in LP mode and then save the important stuff in an SP copy....unless you KNOW the original is all going to be important stuff.

Ken

Try searching the web for "DV IN".

Some links:
http://www.ifrance.com/dv-in-france/
http://lea.hamradio.si/~s51kq/DV-IN.HTM

I made my own cable (very simple) and used a (german?) program with all the necessary steps.
There are also some procedures if anything goes wrong...

I didn't have a problem since the firmware changes and the day after I found those sites I had my Sony completly different... well worth it!

And yes, DV IN function costs a lot in Europe...