I have seen it.. But i can't find the Siig card that has the 9pin connector anywhere in Europe.. I would buy it from Amazon usa but we have crazy shitty customs in Greece and it is going to delay at least 1 month..
Unfortunately that is the only official list of tested cards that I'm aware of. The P65+ is the least-old back for which firewire was the primary/preferred tether method, and it was released in 2008, so there isn't much active testing of firewire cards anymore.
Alternatives include:
- buying random generally-well-rated cards and testing; hopefully from a vendor that accepts returns
- googling to see if any given candidate card is using the same underlying chipset as one of the recommended cards (not a guarantee of operability but as close as you'll get)
- upgrading to an IQ series back. The IQ1-IQ3 use USB3 and the IQ4 offers USB-C and Ethernet as well as wireless raw file transfer
- buying one of the macs (preferably a Mac Pro or Macbook Pro rather than an iMac) that has a native firewire port
But before you do any of these things you should contact the Phase One dealer from whom you purchased the P65+ to troubleshoot the issue with your current hardware. For example, it's possible your firewire card are fine and you can resolve the issue you're having by changing the power settings to Battery (instead of Auto) or using another cable, or updating the back's firmware, or updating the version of Capture One you're using or changing a Capture One setting (like the camera's enabled in the preferences). There are a lot of possible explanations for why your back is not is not connecting (beyond an incompatible firewire card) and it's your dealers job to help you have a good experience with with the back you purchased from them, so don't be shy to use them!