lacie drives

[Simon Carlson-thies]

You have hit the biggest problem of USB… USB2.0 may have a fast spec but in all honesty FW 400 and 800 are better… personally I have a similar situation on my laptop… I use the firewire one for video capture and USB2.0 for a scratch drive and incremental small backups.

The issue comes down to USB2.0 is not fast enough with overheads… to support video capture…

Simon Carlson-Thies,
Digital Light Graphics And Animation

[Rick Broat]

thanks – thought usb 2 would work…. I will try to copy media to the usb drive,(it is the porshe design and much more portable) and edit from there…. if that will work.

[David Slater]

NO USB 2 will NOT work reliably as it doesn’t have fast enough sustained thoughput
use firewire

DAVE at Movies Rock in Toronto

[Simon Carlson-thies]

for a scratch disk it does, unless your doing HD… not for capture there you are correct…

Simon Carlson-Thies,
Digital Light Graphics And Animation

[Rezyser]

hello, i had a different problem with USB 2.0 disk. when compressing audio to AC3 using Compressor 2 i was always getting anoying noise in the whole track. it doesn’t happeen on FW800. i never had any problems with dropped frames. i do edit DV PAL on powerbook g4 1,33 with 768mb ram.

[Simon Carlson-thies]

Are you changing the sampling rate… ie going from 44.1khz to 48.0khz?

Since this problem is not necessarily a HardDrive problem…

Simon Carlson-Thies,
Digital Light Graphics And Animation

[Rezyser]

the audio rate was good, it never happens when i’m using internal drive or FW800 as scratch disk, only on USB 2.0 (i know it sounds strange and it’s an unprofessional diagnosis, but it just happens ;-))

[John Calhoun]

Your problem is more fundamental which doesn’t really have to do with sustained throughput.

USB devices are asynchronous, which means that any device has the power to send any amount of data at any time. If two devices decide to talk at once, their data can collide with each other. If the traffic

[David Bogie]

CAUTION: Joke follows:
> asynchronous, which means that any device has the power to send any amount of data at any time.< That sounds like a sustained throughput problem to me and, frankly, anyone with dropped capture frames can understand that, even if it's not literally true. > One is asynchronous, the other is isochronous mode (signal delivery capability at a specified rate), and guarantees continuous bandwidth without interruption. < As much as we'd love to use this juicy information, it's easier to say "USB doesn't have the sustained throughput required for video." But I swear I'll try to stop using sustained throughput. I shall substitute, erm, "USB2 refuses to respect time-sensitive data flow whereas Firewire has the emotional capacity to deal with such sensitivities." bogiesan This is my standard sigfile so do not take it personally: “For crying out loud, read the freakin’ manual.”

[John Calhoun]

Although “it’s easier to say ‘USB doesn’t have the sustained throughput required for video'”; that doesn’t explain why. I had to clarify because two posts said that USB ‘wasn’t fast enough’, which is technically not true. That’s why people get confused by the different specifications and applications of USB and Firewire. As professionals we try to avoid wasted time and wasted money.

Plus, for crying out loud, it’s not really covered in the freakin’ manual. ;