Issue:
Connecting more than 2 cameras to a 2-port IEEE-1394 card.

Solution:
You can purchase 6-port 1394 hubs that will allow you to put more devices on the same bus. See the Related Article below for a list of 1394 FireWire hub manufacturers. As you continue to add more cameras, if camera performance becomes inconsistent it could be a result of lack of power. Ensure adequate power is reaching each camera.

Related Articles:
1.) Maximum number of IEEE-1394 cameras on a single 1394 bus.
2.) Dragonfly timing characteristics (integration and shutter times).
3.) My laptop's IEEE-1394 port or PCMCIA card doesn’t supply power to my camera.
4.) Using PGR IEEE-1394a cameras with 1394b Open Host Controller interface cards.
5.) Does Point Grey sell FireWire/IEEE-1394 and digital camera accessories?
6.) Extending the distance between a PGR camera and the controlling host system.
7.) Factors to consider when designing a multiple FireWire camera array.