I got very little helpful information with my new Nodal Ninja R1 for installation on a Panasonic 8mm fisheye. Firstly, the instructions are misleading and need to stress that the lens ring cannot be installed from the front. Tried that and scratched the plastic lens hood that is part on the lens. You have to have the lens off of a camera and install the lens ring from the back of the lens. Maybe that is obvious to somebody, but it certainly was not obvious to me and I wasted a lot of time screwing around until I appreciated that fact.
Following the instructions in http://www.johnhpanos.com/epcalib.htm , the no parallax point with this combination of a Panasonic 8mm fisheye lens and the Nodal Ninja R1 appears to be at 1.2 on the scale of the R1.