After yesterday’s post, I got some requests about how well the new Nikon 20mm f/1.8 AFS G Nikkor lens handles chromatic aberration (CA). For the record, when I test a lens, I try not to obsess about lab benchmarks and instead focus on just using the lens. I haven’t been able to go out to use this new lens in a real situation yet, but so far I’ve seen nothing to suggest that this lens isn’t an excellent addition to the Nikkor line.
So, a quick CA test for all the pixel-peepers after the jump.
Here are 100% (1:1) views of CA, with the image captured at f/2.0. As with most lenses, CA, and light fall-off all disappear as you stop down.
Magenta and green fringing extends for 2-4 pixels (D810) at f/2.0. Notice that the color-fringing is only present when I disabled CA removal in Lightroom 5. Once I turned on the automatic CA removal, the color-fringing disappeared. Like light fall-off, these aberrations are really only a problem if you shoot JPEG and don’t apply any corrections to your images. For most photographers, these are non-issues, as they are corrected by a single click in your editing application. In fact, I’ve set up Lightroom to enable CA removal by default for all my cameras, something I cover in my Lightroom 5 guide.