I'm Confused is DV through Firewire A Capture or a Copy

[crash447]

I am confused, I have been reading how a conecting a DV Camcorder through a firewire connection is a copy(transfer) and not a capture. I had thought this was the way it worked until I got my camera and since then I have thoght it was a capture. However the part that really confuses me is that I have always been able to capure(copy) fine until the past week. Now I can not get anything to transfer over right. I drop frames like crazy and I have tried all kinds of programs. I have tried everything I have read on here and am still having no luck. I have shut down my computer for days at a time, defragged, and many other things I have read and still nothing works. I have noticed that the files that are fragmented on my drive are my older videos and I am having trouble getting them unfragmented. Everything on my computer seems to work fine and I can even watch the video fine, but when I start a capture the video just freezes while it is capturing. So I am wondering if this question of Capture or Copy can help me with my problem.
Thanks.

[solarfox]

When dealing with DV-over-Firewire, the terms "capture" and "copy" become a matter of semantic confusion. (Similar to the way "baud" gets misused in describing the speed of a dial-up modem.) Especially when using a camera that does pass-through, or an analog-to-DV device such as a Canopus ADVC or a Dazzle DVbridge.

Strictly speaking, "capture" (IMO) refers to the process of converting the analog video signal into a digital data format. Under this definition, the "capture" process takes place inside your camcorder, and the data is stored on tape; this data is then "copied" from the tape to the hard drive, almost verbatim (save for wrapping the DV data into an AVI wrapper so Windows knows what to do with it). If you're doing pass-through or using an analog-to-DV device, then the tape step is bypassed and you're "copying" data from the device's memory buffers on the fly.

However, colloquially speaking, we do tend to use the word "capture" as a generic catch-all term for getting video from an external device into the computer, regardless of how you go about it.

In any case, no, this isn't going to help you with your problem. One thing you might want to check is to see if your HD is no longer able to sustain the 3.5MB/sec transfer rate you need to do DV capture -- if it's developing a fault and the IDE controller is doing a lot of data shuffling and sector remapping, that'll slow things down. Or something you installed recently may have monkeyed with critical system settings, and you're no longer using DMA access for your hard drives...