View Full Version : analogies of firewire capture=false/true?


Yi Fong Yu
October 26th, 2004, 09:52 AM
i've always heard that firewire is like copying a file from the miniDV tape. if that's true then why not copy it faster than 1x? since it is digital why not have the tape fastforward and let the computer copy it. after all firewire does have the bandwidth.

personally i still think it's more similiar to analog copy in that the miniDV is played back digitally via firewire and the computer is simply capturing the STREAM of the miniDV data. take those backup tapes on servers for example they typically cycle them as fast as the head can read data off of the tapes or write on them.

what do you think?

Peter Moore
October 26th, 2004, 01:07 PM
Firewire has the bandwidth but the camera might not.

Yi Fong Yu
October 26th, 2004, 01:24 PM
well what do you mean? i mean the cams all fast forward and rewind. i don't see why they can't put their heads down and read all the data over firewire and transfer the stream data just like they do with datatapes.

Rob Lohman
October 31st, 2004, 07:09 AM
It just hasn't been engineered to those specs. It skips frames etc.
to get the fast forward. That is one of the issues with things like
tape (and how digital camera's work with them). In theory it might
be possible to make a camera that would support that, but then
it would not support any standard and would need to include a
special capture program (for at least PC and Mac).

So in the end it just isn't going to happen. If time is *that* critical
to you then get a firestore like device and record directly to
harddisk and you can copy (if not working with the original disk)
it at least 5 times as fast.

Glenn Chan
October 31st, 2004, 02:11 PM
There are systems that do 4X transfer with DV tape.


Both Sony and Panasonic have Windows-based, turnkey systems for DVCAM (ES-3, using the former FAST Studio software; ES-7) and DVCPRO (DV Edit, NewsByte) respectively, that exploit the added features of these higher-end DV formats such as 4x transfer and editing metadata (in DVCAM, "ClipLink" good/no-good shot markers and clip picons provided by high-end DVCAM camcorders; in DVCPRO similar data are stored as "Picture Link" information). Prices start around US$25,000 (no real-time 3D effects, no 4x transfer) and go up from there.

http://www.adamwilt.com/DV-FAQ-editing.html
Scroll down to High end "heavy iron"

Yi Fong Yu
October 31st, 2004, 04:26 PM
i just thought that since it is all digital how come they never spec's it for high speed on the low consumer end as well as high end. ah well... keep wishing eh? =). i hope the next HD connection (not HDV) but a newer HD standard should be much faster than this.

Sean McHenry
December 6th, 2004, 11:16 AM
I think it's more related to the speed the decks can handle rather than the cameras. Tape speed that is. To make a tape system play back at faster than standard speed, the tape heads and associated system would have to be a DT (Dynamic Tracking) type and they are much more expensive than standard head systems.

The older, original DSR40-80 series could be connected to each other for faster than realtime dubbing but those decks were a lot of money. Still are.

On the other hand, if you save your video as a file, you can transfer it as an AVI as fast as your machine can handle, but only to another machine (editor), not to a deck. Decks are ready to accept files.

That may be the answer ultimatly. Storage not as tapes but as files. This is exactly what things like the FireStore FS-4 does. You hook it to your camera and record directly to a file. You then can plug the FS-4 by firewire into your system and start editing.

No downloads, no file conversion and there, you can play the file out realtime when you are done. To get it to tape you still need to play it out realtime.

Sean McHenry