Connecting Phase One Digital backs to USB-C and Thunderbolt 3

Summary

There are several ways to connect both over USB-C and Firewire to Phase One and Leaf Credo Digital Backs.

In-Depth

Phase One IQ series and Mamiya-Leaf Credo backs via USB 3.0:

There are several options for connecting tethered to the new MacBook Pro or other USB-C only computers:

1. A USB 3 cable with a USB 3.1 C-connector on one end and USB 3 B-connector at the other end.  Please note that not all USB3 B-connectors will fit into the IQ and Credo digital backs recessed USB port.  The outer mold of the B-connector should not exceed 11,6 x 14mm.
   
2. An adaptor with a USB 3.1 C-connector and an USB 3.0 A-connector. Please note that not all USB adapters adapts to USB3, but some only provide USB2 connections, normally USB3 is indicated by the blue color applied inside the A-connector.  
   
3. OWC Thunderbolt 3 Dock. This dock is available from OWC and offers multiple port connectivity of USB3 A-connectors as well as FireWire. - One advantage in using the OWC docking station is that the IQ digital back can draw 1500 mA on the USB port, and therefore can extend battery life on the IQ back. A normal adapter is only able to draw 900 mA from the USB port. For this feature to work, Charging from PC should be set to Slow and USB Power Management should be set to On in Menu > IQ Settings > Power Management.
    

Phase One IQ, P/P+, and H series backs, as well as Mamiya-Leaf Credo, AFI, and Aptus series backs via FireWire:

A combination of Apple's FireWire to Thunderbolt adapter plus a Thunderbolt 2 to Thunderbolt 3 (USB-C) adapter will NOT work properly (even when Phase One backs are forced to use battery power). Instead a full dock is required. There are two options:

1. OWC Thunderbolt 3 Dock. The version of this dock that had a native firewire port is now discontinued from OWC ,and offers multiple port connectivity of USB3 A-connectors as well as FireWire. The FireWire port is well powered and should be capable of charging the IQ series battery. Go to Menu > IQ Settings > Power management > Charging From PC > Choose "Slow". However, if you have any tethering problems, set "Charging from PC" to "Off." 
   
2. OWC Thunderbolt 2 Dock+ Apple Thunderbolt 2 to Thunderbolt 3 adapter. Even though using a basic FireWire to thunderbolt adapter will not work when converted to USB-C, you can use the OWC Thunderbolt 2 dock with Apple's Thunderbolt adapter. This will provide the same power over FireWire as the Thunderbolt 3 version, so it is compatible with all Phase One and Mamiya-Leaf backs using FireWire.