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50 years of Nikon F-mount – Nikkor-S 5.8 cm f/1.4 vs. Nikkor AF-S 50 mm f/1.4G

7. Coma and astigmatism

A quick glance at the below clippings of the diode placed in different places of the frame shows that we’ve found the first culprit of the weaker edge of the frame performance of Nikkor-S 5.8 cm f/1.4. Coma is enormous in this lens and that’s both in the corner of an FX and a smaller DX sensor. What’s sad, even stopping down by one aperture value doesn’t improve the situation much.

Against this, the results of the new Nikkor AF-S 1.4/50 look very well, especially in the DX corner. Here coma’s corrected the way it’s supposed to. In the corner of a full frame however it is not so good any more and coma is clearly visible.

Nikkor-S 5.8 cm f/1.4

Nikkor AF-S 50 mm f/1.4G

Another of off-axial aberrations– astigmatism – is very sensitive to all inclinations of lenses at the wrong angle to optical axis. And we know that it’s easier for those things in a well-used lens. So in this category, Nikkor S 5.8 cm f/1.4 having worked almost half a century is in a hopeless situation. The result of 15% is not very good, although taking into account the flow of time and intensive operation it’s no shame for the company.

As a comparison, the new and much less used Nikkor AF-S 50 mm f/1.4G came off much better here. Its result is 6%, so a level we recognize as the boundary of a good and a very good.