Which 50mm lens?
Yesterday evening I shot a comparison (scenic at infinity) on the D3x with the Nikon 50/1.4G, Sigma 50/1.4, Zeiss ZF 50/1.4, Nikon 50/1.4D and Voigtlander 58/1.4 Nokton. I was in a rush, as it was dusk and the light was changing steadily, so I had no time for Live View by eye with a loupe, as is my preference. Lenses are extremely hard to compare fairly, and focus is just one of the many challenges, especially out in the field.
The winner: the Zeiss ZF 50/1.4 Planar—it easily showed the best detail and contrast and color, but with a caveat that renders the optical comparison null and void: none of the AF lenses could focus accurately (all front-focused slightly), even with contrast detect AF in Live View, using f/3.5 to preclude focus shift issues. (AF focus accuracy is not a Nikon-specific problem). The Voigtlander 58/1.4 (in-depth review in DAP), apparently is not a good performer at infinity off-center (better at close range), and I have not verified that its infinity stop is perfect—yet another detail when making comparisons.
So how did I focus the Zeiss ZF 50/1.4 Planar? I just set focus at the mechanical infinity stop and the results were perfect. That’s not possible with the Nikon 50/1.4G and SIgma 50/1.4, because they focus well past infinity.
