yCan someone explain to me what difference there is between a cheap firewire card and say a DV500 or the Raptor.Do we pay more for the dearer cards because they have expensive software included in the purchase, or do the dearer cards capture better quality of video.
comments would be appreciated
Thanks to all who replied to my question but John H Jones gave the information I was looking for thanks John.
R Henry
[This message has been edited by r henry (edited 27 July 2001).]
The cheap cards are DV/Fire Wire cards only.
the Expencive cards have real Time editing capebilities and some more Features.
------------------
www.highvid.com
This one was over in the FAQ forum, but although this is a FAQ, I don't think the answer is sufficiently well rounded.
Anyone care to comment further.
Once we've had a few responses, I copy it back over into the FAQ forum.
Bob C
I'll attempt a summary.
1. OHCI cards
Firewire (aka 1394) has now become a commodity interface, like USB. In fact it competes head-head with USB-2. Several chip makers make 1394 interface chips, and some PCs, not to mention Apples, have integral 1394 ports. These ports can connect to a whole range of 1394 devices, video cameras are just one application. OHCI (Open Host Controller Interace) is the control protocol enabling the PC to control a device as well as transfer data. The hardware is general-purpose, mass-produced, thus cheap, and relies on device drivers in the Operating System. It's what Firewire was designed to be.
2. Video Firewire cards
These are 1394 cards made specially for connection to DV camcorders. They appeared before cheap OHCI cards, and generally rely on dedicated drivers to capture video - they can't work with other peripherals. The Canopus DV Raptor is one of the best-known examples.
Some newer dedicated video cards appear to be OHCI cards with extra bits, e.g. analogue output and/or input in addition to 1394. These can be considered to be 2-in-1 devices, i.e. an OHCI 1394 port and an analogue video capture/replay device.
3. Real-time cards
These are dedicated DV cards with the addition of some real-time processing, e.g. merging and cross-fading of two video streams, video filtering, effects, etc. The extent of the real-time features roughly corresponding to the price. These are much more expensive, and can be identified by price and the fact that they have "RT" somewhere in the product name.
That's my take, feel free to correct or augment, I won't be offended 
------------------
Richard Jones, http://www.activeservice.co.uk
Home of the new MediaStudio Pro 6 Tutorial
This is from the old Matrox BB
quote:
IEEE-1394a adds the folling;
1. debounce of the cable connection.
2. standardized PHY-Link interface.
3. added PHY-Link interface features to control new arbitration enhancements.
4. added features to prepare for the even faster 1394b
5. a new standard register map
6. software control over bitfields in the Self-ID packet
7. shortened arbitrated bus reset
8. arbitration enhancements to more fully utilize the available bandwidth
9. multispeed concatenation
10. "Ping" timing for bus arbitration gap optimization
11. capability to disable individual ports
12. suspend/resume capability to manage PHY power consumption. Includes remote read/write and responses.
Most of these improve device compatability, bus stability and overall performance.
Dr. Mordrid
[This message has been edited by Dr Mordrid (edited 17 May 2001).]
Terry is a beta tester of MSP6.5 & seems to know his DV stuff, some of the older OHIC cards aren't 1394a
btw Richard '3. Real-time cards'
How does this work with OHIC & MSP6.5 (Or is it 7)
John Price
http://www.johnpr98.com
[This message has been edited by johnpr98 (edited 27 July 2001).]
Dear Richardj,
Really sorry to buck this thread but have e-mailed you, is your tutorial cd compatable with windows ME?
Regards to all
and very sorry to rHenry.
With regard to DV input and output quality, as I understand it there is no difference between a cheap firewire card and say a DV500 or Matrox RT 2000. Its the DV camera that makes the difference in image quality not the cards.
John
quote:Originally posted by John H Jones:
With regard to DV input and output quality, as I understand it there is no difference between a cheap firewire card and say a DV500 or Matrox RT 2000. Its the DV camera that makes the difference in image quality not the cards.
John
Thanks John your reply is what I was looking for, I have a fair idea about DV device connections to 1394 and real time, I just wanted to know if the cheap card captured from the camera is just as good a quality as capturing from the more expensive cards. So what you are saying is buy a cheap card and get the same quality of capture as say a DV500.
Thanks to all who replied.
Robert Henry
It is sometimes more helpful to see it from the DV device point of view. An OHCI card will demand a correct response to the initial handshake, which includes apparently negotiation to jump to an available channel from the 63 possibilities. (negotiation takes place on Ch63) Any quirks from the norm will need an OS Driver update, for most folks involving Microsoft or Apple.
A dedicated video 1394 card can just worry about the DV device and Drivers can be written to suit by the manufacturer.
The ideal is thus probably an OHCI card or built in to M/B 1394 for general use (including Firewire HDs for video media storage) and a separate card for video 'capture'.
If you have still not bought a card then I suggest that you take a look at www.lynxdv.com and the cards they have on offer.( First class service from Ian- the Boss man).
The Pyro dv card works very well in my set up with Media Pro 6 but if I had a faster computer then I would also be looking hard at the Raptor RT just because of the extra "bells & whistles".
John