How about that: DV tape as a backup medium? at DVinfo.net

Daniel Kissel · June 26th, 2006, 08:32 PM

How about this: use the internal MiniDV tape as a backup drive to download the HD content on the P2 card? I seem to remember that there used to be videotape-based data backup solutions for the PC.

So if the data a MiniDV tape can hold is 25Mb/s for 60 min, wouldn't it technically be possible to save 15 min of 100Mb/s footage?

I mean the infrastructure is all there - all it required was a electronic pathway to save the raw data and then upload it to a computer. To the tape it's just data.

Painfully slow (maybe not with intelligent use of camera downtimes) but also very portable and inexpensive. Might come in handy when you are out in the wilderness, just fresh out of HDD storage space...

Mark Burton · June 27th, 2006, 04:10 AM

This is an interesting idea. To make it most useful you would want to use the maximum LP length of the tape. According to this software http://www.coolatoola.com which does what you describe, you can get 17.5GB on a single 60 min DV tape when you use the LP mode. This has no protection for recovery if there are any issues such as dropouts though.

With full protection in SP mode it only records 5.5GB.

The other thing is that it will take a full 60 minutes to make the backup to this tape. If you did this externally from a Mac and used a larger DVCAM 184 tape and deck you could get 50GB or so with no protection, but its going to take 3 hours to do.

Traditional tape backup I imagine is designed to do essentially the same but with specially designed heads, tapes and control systems so the whole process can be much faster.

Interesting idea though.

Chris Barcellos · June 27th, 2006, 12:05 PM

Boy this cracks me up a bit. But somewhere when P2 was just coming out, we there was a big discussion about how to back up HDV. Ultimately, I said tape drives or some other kind tape back up would have to be the choice-- otherwise P2 users would have stacks of portable hard drives. Of course another answer is Blue Ray as a data disk.

So how about backing up to a Sony HC1 by firewire.

Philip Skaist · July 5th, 2006, 12:13 PM

I've been using DVD-R's. They are pretty quick, and with roxio's spanning feature you can just pop em in one after the next.

Michael Totten · July 8th, 2006, 08:21 PM

Quote:

Originally Posted by Philip Skaist

I've been using DVD-R's. They are pretty quick, and with roxio's spanning feature you can just pop em in one after the next.

How much 1080 or 720 have you been able to store on a single disk?
How long does it take to burn the footage onto a disk?
Have you taken footage back off of the disk? If so how long does that take? Is the footage stored in it's native DVCPRO format or is it compressed into something else? Data?

Thanks!
Michael

Philip Skaist · July 9th, 2006, 03:12 PM

I've only been shooting 720 native (pn?) and in that mode you can fit 10 minutes of 720 24p on a 4 gig card. a dvd-r holds 4.7 gig. I usually put one 4 gig card per dvd.

Michael Totten · July 10th, 2006, 01:33 PM

Quote:

Originally Posted by Philip Skaist

I've only been shooting 720 native (pn?) and in that mode you can fit 10 minutes of 720 24p on a 4 gig card. a dvd-r holds 4.7 gig. I usually put one 4 gig card per dvd.

How long does it take to burn it to DVD?

Philip Skaist · July 10th, 2006, 02:10 PM

Well that all depends how you back up. At first I was copying the actual p2 card to my desktop and then burning that file to DVD. Now, some people are saying that they've had problems retrieving the files that way (corrupt files?) they say the new work flow from apple is to create a disk image of the p2 first and then burn that to DVD. That would take much longer, so what i've been doing until I have a better/quicker solution is importing the p2 data into fcp and burning the unwrapped .mov files to disk. So the import takes a few minutes and burning to DVD takes about 10-15 minutes (i haven't paid close attention to that part)

Michael Totten · July 10th, 2006, 08:49 PM

Quote:

Originally Posted by Philip Skaist

Well that all depends how you back up. At first I was copying the actual p2 card to my desktop and then burning that file to DVD. Now, some people are saying that they've had problems retrieving the files that way (corrupt files?) they say the new work flow from apple is to create a disk image of the p2 first and then burn that to DVD. That would take much longer, so what i've been doing until I have a better/quicker solution is importing the p2 data into fcp and burning the unwrapped .mov files to disk. So the import takes a few minutes and burning to DVD takes about 10-15 minutes (i haven't paid close attention to that part)

Thnanks for the info. I'm just trying to figure out how long the archiving to DVD part of my workflow is going to take. I hope to comit to a more long term solution soon. Still weighing all out. LTO/DLT looks good to me.

June 26th, 2006, 08:32 PM	#1
Daniel Kissel Regular Crew Join Date: Mar 2006 Location: Suzhou, China Posts: 34	How about that: DV tape as a backup medium? How about this: use the internal MiniDV tape as a backup drive to download the HD content on the P2 card? I seem to remember that there used to be videotape-based data backup solutions for the PC. So if the data a MiniDV tape can hold is 25Mb/s for 60 min, wouldn't it technically be possible to save 15 min of 100Mb/s footage? I mean the infrastructure is all there - all it required was a electronic pathway to save the raw data and then upload it to a computer. To the tape it's just data. Painfully slow (maybe not with intelligent use of camera downtimes) but also very portable and inexpensive. Might come in handy when you are out in the wilderness, just fresh out of HDD storage space...

June 27th, 2006, 12:05 PM	#3
Chris Barcellos Inner Circle Join Date: Nov 2005 Location: Elk Grove CA Posts: 6,838	Boy this cracks me up a bit. But somewhere when P2 was just coming out, we there was a big discussion about how to back up HDV. Ultimately, I said tape drives or some other kind tape back up would have to be the choice-- otherwise P2 users would have stacks of portable hard drives. Of course another answer is Blue Ray as a data disk. So how about backing up to a Sony HC1 by firewire. __________________ Chris J. Barcellos

June 27th, 2006, 04:10 AM	#2
Mark Burton New Boot Join Date: Nov 2004 Location: London, UK Posts: 10	This is an interesting idea. To make it most useful you would want to use the maximum LP length of the tape. According to this software http://www.coolatoola.com which does what you describe, you can get 17.5GB on a single 60 min DV tape when you use the LP mode. This has no protection for recovery if there are any issues such as dropouts though. With full protection in SP mode it only records 5.5GB. The other thing is that it will take a full 60 minutes to make the backup to this tape. If you did this externally from a Mac and used a larger DVCAM 184 tape and deck you could get 50GB or so with no protection, but its going to take 3 hours to do. Traditional tape backup I imagine is designed to do essentially the same but with specially designed heads, tapes and control systems so the whole process can be much faster. Interesting idea though.

July 5th, 2006, 12:13 PM	#4
Philip Skaist Regular Crew Join Date: Feb 2004 Location: Lakewood, NJ Posts: 41	I've been using DVD-R's. They are pretty quick, and with roxio's spanning feature you can just pop em in one after the next.

July 9th, 2006, 03:12 PM	#6
Philip Skaist Regular Crew Join Date: Feb 2004 Location: Lakewood, NJ Posts: 41	I've only been shooting 720 native (pn?) and in that mode you can fit 10 minutes of 720 24p on a 4 gig card. a dvd-r holds 4.7 gig. I usually put one 4 gig card per dvd.

July 10th, 2006, 02:10 PM	#8
Philip Skaist Regular Crew Join Date: Feb 2004 Location: Lakewood, NJ Posts: 41	Well that all depends how you back up. At first I was copying the actual p2 card to my desktop and then burning that file to DVD. Now, some people are saying that they've had problems retrieving the files that way (corrupt files?) they say the new work flow from apple is to create a disk image of the p2 first and then burn that to DVD. That would take much longer, so what i've been doing until I have a better/quicker solution is importing the p2 data into fcp and burning the unwrapped .mov files to disk. So the import takes a few minutes and burning to DVD takes about 10-15 minutes (i haven't paid close attention to that part)