I tried sharpening the reflection photo to take a look (enclosed). I am
hooked on w - i - d - e , but I use the 15 less than I did (and the 16 more).
BTW, the two Nikkor 15's are quite different - the f5.6 is more even to the
corners, especially in B&W; the f3.5 is sharper across the frame, but poorer
in the corners; the f3.5 is Nikkor-normal in color; the f5.6 is a bit yellow;
the f5.6 is nearly distortion-free; the f3.5 has the wavy-line distortion;
the f5.6 can show a purple arc from skylight out of frame (can be shaded out
with a hand), and shows more ghosting from light sources; the f3.5 is true-speed
and meters correctly; the f5.6 is about 1/2 stop slow, and also meters about
1/2 stop too dark; I prefer the f5.6...