When using a default VR camera rig with Target Eye set to "Both" the IPD is automatically applied to the left and right views. Is this still the case when you setup a custom rig with two separate cameras that have Target Eye set to "Left" and "Right"? In other words does each camera automatically get offset by half of the IPD or does the offset have to be manually applied by the transforms in the custom rig? Is there any documentation that covers how IPD is applied? I'm guessing it's been done by a modification to the view matrix but I'd like to get some more details.