How long does it take to offload a SxS card?
by Steve Weber
on
Jul 3, 2009 at 9:26:35 pm
So we are shooting with 32GB SxS cards on a shoot here and I was wondering if anyone has ever timed the offload time it takes to offload 1 of these cards?
From what I have found if the 32GB card is full, it will take about 32 minutes to offload. Has anyone else found anything different then this? Has anyone else even bothered to measure this?
Re: How long does it take to offload a SxS card? by Craig Seeman on Jul 3, 2009 at 10:20:00 pm
There are various factors like Express port vs USB and the speed of the hard drive you're going to and CRC checking cuts the speed in half but 4x faster than real time (up to 2x faster with CRC off but not advised). 32GB (2 hours) could be dumped in a half hour with CRC on thorough Express port.
I get twice faster than real time with 32GB SDHC through USB with CRC on.
Re: How long does it take to offload a SxS card? by Bengt-Goran Bengtsson on Jul 7, 2009 at 9:21:41 pm
why do you have crc on? I have never seen any error. What happens when it appears?
I have a Sony Vaio VGN-Z31WN and when I do a drag and drop of the BPAV directory to the internal hard drive it starts on unloading the SxS card at 100MB/s (I guess into the RAM memory), then it drops down to 34MB/s giving 16min for a full 32GB card. The hard drive is capable of 80MB/s. If it was possible to lock the system to only handle the transfer it should transfer 32GB in less then 7minutes.
Maybe Sony would think about it. The cheap SD card solotion whould then be (a little) less interesting.
We need a direct drive to drive transfer mode, I think.
But anyway, the Express port is still x2 of the effective USB speed...
/BG
Re: How long does it take to offload a SxS card? by Craig Seeman on Jul 7, 2009 at 9:31:51 pm
[Bengt-Goran Bengtsson]"why do you have crc on? I have never seen any error. What happens when it appears? "
Some people have never been in a car accident. You do tend to know it when it hits you though. There are as many types of errors as there are car accidents. Ranges from metadata issues to unplayable (and unsalvageable) clips. Of course at that point, like the car accident, it may be too late. You'll have wished you wore the seatbelt and used CRC On.
Like driving a car, the more you do it the more it's a possibility that the accident will happen once. Like a car accident, once can be fatal for the shoot, your client, your business.
BTW there are all sorts of bottlenecks when copying files so it's hard to say what you're seeing. Sony reported a long while back of something like a max of 8x or was it 10x using a Vaio (I forget which model) to RAID 0 Striped drives. With SxS I get 4X with CRC on my MacBookPro, and I think it was 6X with it off but I don't drive without a seatbelt.
