LP/SP with XL2 at DVinfo.net

Mark Errante · March 13th, 2005, 10:40 AM

Is there going to be a noticable quality loss with LP. Iv never used it but am faced with a dilema. I will be shooting a concert were the band often runs one song into another, sometimes going for a half hour with out ever stopping. Ontop of that, they dont use a playlist, they just pick songs on the fly. I will have 4 cams going. I dont want to use LP but thought I would see if you all had any experience with it. Thanks!

Marcus

Barry Green · March 13th, 2005, 11:07 AM

LP records an identical signal, bit-for-bit the same as SP. It's not like VHS where LP is noticeably degraded; in DV LP is the same as SP.

However, there are drawbacks to LP mode: it's much more prone to dropouts, and there's no guarantee that an LP recording made in one camera will play back on any other camera or deck. The manuals of most/all DV cameras even spell that out -- LP recordings are only supposed to be played back in the camera that made them in the first place, any playback in any other camera/deck isn't guaranteed. And many decks won't even try to play LP tapes.

For longer recording times you have four options: LP mode, or using the 80-minute DV tapes, or recording to hard disk, or to a deck. LP mode's advantage is 50% longer record times, and the disadvantages are listed above. 80-minute DV tapes give you a 33% longer recording time, but at the risk of crinkling due to thinner tape stock. Hard disk recording (such as a FireStore or nNovia QuickCapture) can give you three to six hours of continuous record time, reliably, but the drawback there is cost -- a 3-hour hard disk recorder might cost $800 or more. The fourth option is recording through firewire on an external deck, with the deck using large DV tapes. The large DV tapes can store four and a half hours of recording. Deck rental should be fairly cheap, so this might be an option to consider as well.

Mark Sasahara · March 13th, 2005, 11:20 AM

The quality drop is significant. Stick with SP.

I suggest tape changes after each song, but stagger when each camera changes, so that at least two other cams are rolling to cover that down time. Perhaps the cameras that are covering wider shots should do that and the cams that are covering close ups can keep shooting and change whenever. Just always be sure at least one camera is rolling at all times.

If you have a Clearcom headset, or other two way communications for each operator that would help, because then all the ops can communicate with each other. Just be sure that they aren't screaming at each other and interrrupting the performance. Also radio keeping discipline is good too, no talking unless necessary, no joking around, etc. Some of the cheap walkie talkies have a jack for a headset and work pretty well. Just be sure to have extra batteries for each one. Check some of the rental houses, theatrical places may also have this kind of gear too.

It may be a good idea to have an assistant with each camera to help the operator.

Chris Hurd · March 13th, 2005, 12:07 PM

There is no difference at all in image quality between SP and LP. Image quality is identical in SP and LP modes. The primary disadvantages of LP recording have been described very well by Barry Green above. Hope this helps,

Frank Aalbers · March 13th, 2005, 12:42 PM

Logically I would think there is no quality loss since both are the same digital stream with the same compression. It's just the medium that will not be as secure in LP as in SP because you try to cram the same data on less tape space. Hence bringing up the possibility of dropouts.

Frank

March 13th, 2005, 10:40 AM	#1
Mark Errante Regular Crew Join Date: Jan 2005 Location: St. Louis MO Posts: 62	LP/SP with XL2 Is there going to be a noticable quality loss with LP. Iv never used it but am faced with a dilema. I will be shooting a concert were the band often runs one song into another, sometimes going for a half hour with out ever stopping. Ontop of that, they dont use a playlist, they just pick songs on the fly. I will have 4 cams going. I dont want to use LP but thought I would see if you all had any experience with it. Thanks! Marcus

March 13th, 2005, 11:20 AM	#3
Mark Sasahara Major Player Join Date: Oct 2004 Location: NYC Posts: 649	The quality drop is significant. Stick with SP. I suggest tape changes after each song, but stagger when each camera changes, so that at least two other cams are rolling to cover that down time. Perhaps the cameras that are covering wider shots should do that and the cams that are covering close ups can keep shooting and change whenever. Just always be sure at least one camera is rolling at all times. If you have a Clearcom headset, or other two way communications for each operator that would help, because then all the ops can communicate with each other. Just be sure that they aren't screaming at each other and interrrupting the performance. Also radio keeping discipline is good too, no talking unless necessary, no joking around, etc. Some of the cheap walkie talkies have a jack for a headset and work pretty well. Just be sure to have extra batteries for each one. Check some of the rental houses, theatrical places may also have this kind of gear too. It may be a good idea to have an assistant with each camera to help the operator. __________________ Mark Sasahara Director of Photography

March 13th, 2005, 12:07 PM	#4
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,368 Images: 513	There is no difference at all in image quality between SP and LP. Image quality is identical in SP and LP modes. The primary disadvantages of LP recording have been described very well by Barry Green above. Hope this helps, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

March 13th, 2005, 11:07 AM	#2
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	LP records an identical signal, bit-for-bit the same as SP. It's not like VHS where LP is noticeably degraded; in DV LP is the same as SP. However, there are drawbacks to LP mode: it's much more prone to dropouts, and there's no guarantee that an LP recording made in one camera will play back on any other camera or deck. The manuals of most/all DV cameras even spell that out -- LP recordings are only supposed to be played back in the camera that made them in the first place, any playback in any other camera/deck isn't guaranteed. And many decks won't even try to play LP tapes. For longer recording times you have four options: LP mode, or using the 80-minute DV tapes, or recording to hard disk, or to a deck. LP mode's advantage is 50% longer record times, and the disadvantages are listed above. 80-minute DV tapes give you a 33% longer recording time, but at the risk of crinkling due to thinner tape stock. Hard disk recording (such as a FireStore or nNovia QuickCapture) can give you three to six hours of continuous record time, reliably, but the drawback there is cost -- a 3-hour hard disk recorder might cost $800 or more. The fourth option is recording through firewire on an external deck, with the deck using large DV tapes. The large DV tapes can store four and a half hours of recording. Deck rental should be fairly cheap, so this might be an option to consider as well.

March 13th, 2005, 12:42 PM	#5
Frank Aalbers Regular Crew Join Date: Oct 2004 Location: Oakland,CA Posts: 135	Logically I would think there is no quality loss since both are the same digital stream with the same compression. It's just the medium that will not be as secure in LP as in SP because you try to cram the same data on less tape space. Hence bringing up the possibility of dropouts. Frank