Gerald, IMO yes the 35mm shift is the key lens for the Hartblei Hcam and the Alpa FPS systems with full format 645 sensor because it relates to the view angle of a 24mm shift lens for 24x36mm cameras. And that's the most important view angle for architecture and interior design photography work. Due to the fact that the tech lenses don't work with shift on the Hartblei or the Alpa FPS cams, I was looking for an alternative lens with sufficient flange distance and image circle.
When I saw the Photodo MTF measurement of the Contax 645 35f3.5 Distagon I thought if the MTF is so very high still at the corner of the 645 image circle this could mean that the real image circle is larger and therefore could be useful as a shift lens for 645 full format sensors.
So I asked Mirex if they could produce a custom made Contax 645 to Canon EF shift adapter for me and they agreed. The adapter matches super precisely the register difference between Contax (64mm) and Canon (44mm). I tested the adapter first on the Canon 5d2 where I saw that the image circle of the Contax 35 easily covered the +-16mm shift movement.
Later I had the opportunity to test the lens with the adapter on a Hartblei HCam B1 with a Leaf Credo 80 at the friendly Leaf/Nexor dealer Alwick in Guangzhou.
I added some green lines to the pano pic of that test that I posted before.
The center area is the sensor unshifted.
The right edge is the image 16mm shifted which is not fully covered by the image circle of the lens.
The two other lines show roughly the 80mm total image circle (= 7mm hor shift or 9mm vert shift) and the 76mm sharp image circle (= 5mm hor shift or 6mm vert shift).
These shift movements are less than one can achieve with the 32mm Rodenstock lens on a tech cam but more than with the 35mm Schneider.
From the lens section view graphics you see how much farer away the 35mm Contax lens sits from the sensor than the two other lenses and therefore don't require LCC files.
When I saw the Photodo MTF measurement of the Contax 645 35f3.5 Distagon I thought if the MTF is so very high still at the corner of the 645 image circle this could mean that the real image circle is larger and therefore could be useful as a shift lens for 645 full format sensors.
So I asked Mirex if they could produce a custom made Contax 645 to Canon EF shift adapter for me and they agreed. The adapter matches super precisely the register difference between Contax (64mm) and Canon (44mm). I tested the adapter first on the Canon 5d2 where I saw that the image circle of the Contax 35 easily covered the +-16mm shift movement.
Later I had the opportunity to test the lens with the adapter on a Hartblei HCam B1 with a Leaf Credo 80 at the friendly Leaf/Nexor dealer Alwick in Guangzhou.
I added some green lines to the pano pic of that test that I posted before.
The center area is the sensor unshifted.
The right edge is the image 16mm shifted which is not fully covered by the image circle of the lens.
The two other lines show roughly the 80mm total image circle (= 7mm hor shift or 9mm vert shift) and the 76mm sharp image circle (= 5mm hor shift or 6mm vert shift).
These shift movements are less than one can achieve with the 32mm Rodenstock lens on a tech cam but more than with the 35mm Schneider.
From the lens section view graphics you see how much farer away the 35mm Contax lens sits from the sensor than the two other lenses and therefore don't require LCC files.
The problem with that setup is that it is not a good solution for shooting RZ handheld which I do quite often! If on tripod, yeah maybe fine since working with RZ make me slow already and if I use the loupe to check focus every single time, I'm sure it makes the model tired and bored! 
