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View Full Version : Maximum length of the firewire cable



ray@frontier
December 16, 2006, 13:39:21
I use DMK 31AF03 and DMK 31BF03 and the provided software of IC control 2.0 to test the live mode quality, but I have unsatisfied result with increase in length of the firewire cable as following:

2.7 m cable: smooth image in live mode without any noise
3.3 m cable: ghost image at the bottom of screen
5 m cable: cannot detect the camera at all

Does anyone have the experiences of successfully use the camera with long cable??

Stefan Geissler
December 18, 2006, 09:53:39
Ray,

Thank you for your interesting input. The guaranteed maximum cable length that is defined by IEEE1394 is 4.5m. Thus, I am surprised about you having problems with 3.3m. The symptoms you describe are known only if there are data blocks are not transferred between FireWire the board and memory. If this happens you see the lower edge of the image moving up and down. It is completely new for me that this could be caused by a FireWire cable. We have a FireWire board / main board combination that shows the same problem independent by the cable length. A parallel connected FireWire bus analyzer showed that all image data have been transferred from the camera correctly to the FireWire board.

At least I tested the cameras with a 10m cable and two 10m cables with a hub (20m complete) without problems. May be you could use a FireWire board with another chip set than the one you are using right now. This could give better results.