"optical formular" in the first paragraph.
I wonder how this lens performs when you really correct CA ? (shrinking the colour channels to same size)
With such high values it must impact resolution too, besides contrast.
Still a good looking 20mm, though.
Any kit lens would probably have better resolution though... The 18-55 VR sure looks better in this regard (at 18 or 24mm), but of course has worse distortion. But a lot of people I know are using this 20mm on FX (D3/D4) for some reason.
How does it come, that the 20mm lens on the D3X performed significantly better? Even the actual 16-35mm was not rated better!