Keep it parallel.
In the course of testing these lenses, it became clear that optical alignment when shifting might be an issue: whether focal plane and sensor are actually parallel and whether they remain so when the lens is shifted.
Misalignment could also potentially ensue when the lens is rotated. This problem is potentially worse with the PC-Nikkors, because rotation is required if stitching center/left/right frames for a composite image, as compared with the Schneider, which has bi-directional shifts.
The test frame further below was taken in portrait orientation with 11mm vertical shift. It was used to determine whether sharpness was consistent across the frame when these lenses were shifted. This was not the original goal for this shot, but the discovery of inconsistent sharpness across the frame made it the goal.
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