Not very scientific, but here goes. Cat statue set on a box, D300 an a tripod, snapped off one shot at each f-stop. Camera on aperture priority. Resized for web and one quick level adjustment. Otherwise no adjustments at all. Jpeg fine, auto WB.

Also on this page are 4 side by sides of the two lenses at the same aperture setting. The CV 40mm is on the left in each case and the Nikkor 50mm is on the right.
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