There is a lot of CA in that example, but it's a pretty tough shot. What are your thoughts so far?
This was a prototype lens I tested, it was raining so this is a quick interior at Canon head office. It is possible that production samples have been tweaked although I don't know how likely that is. Compared to my 17-40 zoom or 24TSE, it had far less CA and virtually no barrel distortion or vignetting. Bear in mind also that @ 12mm rise this is an extreme angle of view, equivalent to half the vertical dimension of the frame. My 58 Schneider can't accomplish the equivalent on 4x5. Sharpness in the center about the same as the 17-40, but the corners were better.