STOP THE PRESS---> How long does it take P2 to transfer to my on-set/field laptop???

Sasha Aickin · April 14th, 2005, 03:06 PM

I think this stat of 4 minutes for 4 GB has been taken out of context, misinterpreted, and repeated by a lot of folks on message boards as of late.

As far as I know, it comes from Panasonic saying that it will take 4 minutes to transfer a 4 GB P2 card on to their new portable hard drive off-loader. However, this is almost certainly due to the speed of the hard drive, NOT the speed of the P2 card.

On Panasonic's web site, they list the data rate of the 4 GB card as 640Mbps (https://eww.pavc.panasonic.co.jp/pro-av/sales_o/p2/p2card/index.html) . If you are recording 1080p30 or 1080i60, this means that it can potentially transfer the footage at 6.4x real time. For 720p24 (assuming that junk frames aren't captured to the P2 card), you can potentially transfer the footage 16x real time.

Of course, if the hard drive you are offloading the data to is slower than 640Mbps (as it is in the case of the portable hard drive Panasonic is marketing), then the transfer will happen more slowly.

Chris Hurd · April 14th, 2005, 03:40 PM

That was an extremely worthwhile contribution from a first-time poster, Sasha. Welcome to DV Info Net. Hope to hear more from you soon,

Thomas Smet · April 15th, 2005, 09:20 AM

That equals roughly 80 MB/S. That type of speed is usually only reachable on hard drives at a sustained rate on a raid 0 setup of 2 or more drives. Even a 2 drive setup may have trouble getting to that level of a sustained transfer rate. For example the G-raid external raid gets a sustained write rate of around 50 to 60 MB/S with using 2 drives. In order to get a 80 MB/S copy rate from P2 you would almost need a raid-0 with 4 drives or a really good hardware raid-5.

A 5400 RPM laptop drive will struggle to reach decent speeds.

If you have a laptop with 2 7200 RPM drives in a raid-0 you may get roughly 40 MB/S or a little under 2 minutes to transfer a 4 GB P2 card.

April 14th, 2005, 03:40 PM	#17
Chris Hurd Obstreperous Rex Join Date: Jan 2001 Location: San Marcos, TX Posts: 27,366 Images: 513	That was an extremely worthwhile contribution from a first-time poster, Sasha. Welcome to DV Info Net. Hope to hear more from you soon, __________________ CH Search DV Info Net \| 20 years of DVi \| ...Tuesday is Soylent Green Day!

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April 14th, 2005, 03:06 PM	#16
Sasha Aickin Tourist Join Date: Jan 2005 Location: San Francisco, CA, USA Posts: 1	I think this stat of 4 minutes for 4 GB has been taken out of context, misinterpreted, and repeated by a lot of folks on message boards as of late. As far as I know, it comes from Panasonic saying that it will take 4 minutes to transfer a 4 GB P2 card on to their new portable hard drive off-loader. However, this is almost certainly due to the speed of the hard drive, NOT the speed of the P2 card. On Panasonic's web site, they list the data rate of the 4 GB card as 640Mbps (https://eww.pavc.panasonic.co.jp/pro-av/sales_o/p2/p2card/index.html) . If you are recording 1080p30 or 1080i60, this means that it can potentially transfer the footage at 6.4x real time. For 720p24 (assuming that junk frames aren't captured to the P2 card), you can potentially transfer the footage 16x real time. Of course, if the hard drive you are offloading the data to is slower than 640Mbps (as it is in the case of the portable hard drive Panasonic is marketing), then the transfer will happen more slowly.

April 15th, 2005, 09:20 AM	#18
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	That equals roughly 80 MB/S. That type of speed is usually only reachable on hard drives at a sustained rate on a raid 0 setup of 2 or more drives. Even a 2 drive setup may have trouble getting to that level of a sustained transfer rate. For example the G-raid external raid gets a sustained write rate of around 50 to 60 MB/S with using 2 drives. In order to get a 80 MB/S copy rate from P2 you would almost need a raid-0 with 4 drives or a really good hardware raid-5. A 5400 RPM laptop drive will struggle to reach decent speeds. If you have a laptop with 2 7200 RPM drives in a raid-0 you may get roughly 40 MB/S or a little under 2 minutes to transfer a 4 GB P2 card.