[MacDV] Internal drive speed for video capture

[Michael Winter]

On Dec 9, 2003, at 9:16 AM, David Crump wrote:

> I was wondering what is the minimum speed required for an internal 
> hard drive for video capture without dropped frames?

I've done it on a stock 450 MHz iMac DV without trouble -as long as the 
drive isn't too full and too fragmented. I don't think the drive speed 
is much of a problem anymore -and hasn't been for quite some time. This 
is just MO, and others may think differently.

>  I always hear that 7200rpm is best for Firewire drives, but does it 
> make a difference if it is an internal drive?

AFAIK, it will make more of a difference on an internal drive than a FW 
drive, primarily because the FW drive is limited by the bus speed 
(Firewire 800 is another matter). I don't remember if the stock drive 
in the iMac DV was a 5400 or 7200 rpm drive, but it is fast enough. 
Another data point is that I've had no trouble capturing to an old 60 
GB Firewire drive that has a 5400 rpm mechanism.

I guess the point I'm trying to make, is that with a "classic" iMac, or 
most Macs for that matter, the drive speed isn't going to be the 
limiting factor. The only times having the fastest drive matters is 
when copying or duplicating a project or when exporting to full quality 
DV. Other than that, any encoding process is going to be limited by 
processor speed, and video capture can only happen in real time, so no 
problem there either.

>  I am just concerned that if I get a Canon ZR 60 it may not be able to 
> capture to an external firewire drive.  If I end up with this problem, 
> then my only other option is the internal drive.  With an older iMac 
> with a slower hard drive, are my only options replacing the internal 
> drive or getting a non-Canon Camera?

AFAIK, any iMac with Firewire (iMac DV and beyond) has an internal 
drive that's plenty fast for capture. The problem is that most come 
stock with 10-12 GB drives (IIRC) and that doesn't hold much digital 
video. By the time you take out the space for the operating system and 
applications, you'd be lucky to get 30 min of video on the drive. I've 
had very good luck using a 450 MHz iMac DV for capture to an external 
FW drive, but that's not using a Canon camera, so YMMV.

-Mike