The image was taken at f/1.4, and studying it gets curiouser and curiouser (apologies to anyone named Alice).
Through serendipity, the focus for this example happens to demonstrate the varying zone of sharpness of the 24/1.4L II (field curvature). Sharpness varies very noticeably at similar distances, from obviously blurred to fully sharp, depending on the offset from center—field curvature.
Metreon area at night, San Francisco
Adobe Camera Raw 8.8.0 (397). ACR settings. Camera Profile = Camera Portrait.
The camera was tilted slightly down, which aligns the plane of focus to more distant areas at top, and closer areas at bottom.
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