Lloyd Chambers (digllloyd) in his tests says Olympus glass cannot cover a frame bigger than 4/3 image circle. There were some rumors Olympus would build a larger than 4/3 frame camera (E7?)
I would like to know how Mr Chambers mounted the 14-35 Zuiko on his D800 and where do those baffles (rectangular shades limiting the image circle) come from.
I built a simple camera obscura (box , tape, sheet of paper), set the Zuiko to the same parameters (25mm, infinity focus) and took some pictures of the image projected on my paper screen (under a blanket).
No baffles. The image circle I got is ca 32 mm. Enough to cover the APS-C frame.
I did not measure how the diameter changes with the focal length.