When I first switched from Pentax to Nikon two years ago I was excited to get my hands on the 85mm f/1.8 AF D as an affordable and compact fast portrait lens. In not too long I found a perfectly used copy on Kijiji and picked it up on a sunny Autumn Saturday. While I liked the lens overall, I didn’t LOVE it. I found the colour to be poor, high chromatic aberrations (specifically longitudinal aberrations, aka bokeh fringing) and susceptibility to flare. The straight-edged aperture blades meant that stopping down gave poor bokeh. Wide open I wasn’t fan of the bokeh either. The screw-driven autofocus, while fast, lacked the accuracy of AF-S. In the end I sold it.
This past weekend I picked up it’s replacement, the 85mm f/1.8 AF-S G. So, what does the updated lens get me?
Sharpness. Online tests have shown this lens to be extremely sharp. Photozone measures the G version to be as sharp at f/1.8 as the D is at f/2.8. In fact, the edges of the D lens don’t match the G’s edges at f/1.8 until f/4. After a week with the lens I concur. It’s consistently sharp at every aperture. Now as I’ll show later, aberrations and low depth of field do reduce the apparent sharpness at wide apertures. Below are a couple of images of the cat at f/1.8 indoors at ISO 800.
The only negative aspect of this lens that I’ve come across so far is bokeh fringing. In fact, I don’t see it as any better over the D version. The image below, at f/1.8, shows the purple and green colours that appear in either side of the focal plane.
Fortunately image editing software, such as Lightroom 4, have a correction tool for both lateral and longitudinal chromatic aberrations. Here is a stress condition of an extremely backlit subject both before and after Lightroom 4’s lens corrections. While the tool doesn’t remove the purple and green fringes completely it makes for a much more natural looking image.