Hi guys -
Sorry for the brief responses to this thread, but as you might imagine we've been incredibly busy with this test. We started yesterday morning at 9am, finished at around midnight and have been at it for about the same amount of time today.
We had the Google+ hangout and it was well attended, sorry if you tried to get on but found it was full.
I'll let you know the basic conclusion now, and will provide more details in a few days when we have the video live and the detailed article written up.
Essentially, at 40x60", the D800E with the 24mm PC-E lens is extremely close to the IQ180 with the 35mm Schneider on the Arca-Swiss. Close enough that at a 'normal' viewing distance of 4-5 feet, you can't tell which is which.
At close viewing, less than about 2 feet, the difference becomes apparent. But it is nowhere close to what you would expect.
In 20x30" prints, the difference is also apparent, but you have to be less than a foot from the print to tell.
I'm gobsmacked, to say the least.
Dynamic range is, as far as I can tell, at least equal between the cameras. Colour rendition appears to be better on the IQ180.
Bear in mind, the IQ180 we were testing is my own. We borrowed the D800 and D800E from friends and colleagues. So I'm giving this result as an IQ180 owner.
Cheers,
Peter