Due to the terrible internet connection where I am at the moment, I'm only now being able to watch the video, albeit in short chunks at a time.
With regards the challenges of shooting in portrait mode (10'50"), would it not be simpler to rotate the back mount through 90 degrees, or am I missing something obvious here?
I had the same question: it's a 6:4.5 shutter, so rotating the back won't work.
Mike.