Comparação da Sigma com Nikkor 35mm 1.4 - TB do Lloyd
Conclusions
Particularly with the crops, the reader should self-remind that this is a 36-megapixel camera. The peak sharpness delivered by ƒ/5.6 by both lenses is astonishing, and speaks well to the potential for a 72 megapixel DSLR. On the flip size, that sharpness is realized within a strictly limited zone (depth of field) and rigorously precise focus is required to realize sharpness where intended.
The sharpness or unsharpness of each lens once stopped down a bit has as much to do with the precise subject placement versus field curvature as anything else. Both lenses are capable of high quality imagery. That said, the Sigma really impresses with its high contrast in the ƒ/1.4 - ƒ/2 range; by ƒ/2.8 - ƒ/4 the Nikon 35/1.4G is closing the gap though it does lag in several respects.
For precise focus, one must consider practical obstacles to peak sharpness: chromatic errors such as LOCA and SLOCA play a role in how crisp the image looks at wider apertures as does overall micro contrast: here the Sigma 35/1.4 is demonstrably superior both in the crops shown here but also in real life when using Live View to focus; the Sigma 35/1.4 image just snaps into view very nicely, the Nikon 35/1.4G image is not quite so clear.
Sigma 35/1.4 DG HSM
The Sigma 35/1.4 DG HSM shows a much lower level of LOCA and SLOCA, so much so that wide open the black lettering could almost be called neutral black (where it is in focus near “14”). The contrast of coarse and fine structures is relatively high, due to some extent to the excellent control of color aberrations. The magenta color cast in the foreground in particular is impressively low. Whether the source of the excellent color correction is due to lens coatings or other factors or both cannot be determined here.
Nor is the Sigma 35/1.4 an laggard in the bokeh department: its high level of color correction contributes a pleasing neutrality that combine with the other pleasing blur qualities: a general avoidance of harsh edges or harsh transitions.
Stopping down to ƒ/2, the Sigma 35/1.4 delivers impressive micro contrast, though not yet at peak levels. Also at ƒ/2, the level of foreground/background SLOCA is reduced to an impressively low level. Many Leica M ƒ/1. 4 lenses and even the M ƒ/2 APO lenses would be hard pressed to perform as well at ƒ/2 in terms of SLOCA.
By ƒ/2, sharpness on the eye is quite high. Stopping down to ƒ/2.8 - ƒ/4, the results are nothing short of superb. Secondary LOCA at ƒ/2.8 is minimal and effectively banished at ƒ/4.
It’s hard to find much to criticize at any aperture with the Sigma 35/1.4 DG HSM here. It is clearly an exceptional lens that can run with the best.
Nikon AF-S 35/1.4G
The Nikon AF-S 35/1.4G is well corrected for LOCA, being largely free of any violet haze effect. However, it shows notably more magenta/green SLOCA than the Sigma 35/1.4 DG HSM and its micro contrast at wider apertures is not at the level of the Sigma 35/1.4. It also shows more lateral chromatic aberration (not a lot of it, but perfectly visible).
At ƒ/4, the Nikon is very sharp on par with the Sigma 35/1.4, but the Nikon shows some residual SLOCA manifesting in high contrast areas including the blurred part of the white ruler. By going to ƒ/5.6 the Nikon 35/1.4G produces a very high quality image; but compared to the Sigma its results in the ƒ/1.4 - ƒ/2.8 range are not compelling and presumably a good part of the appeal of an ƒ/1.4 lens is for peak results over the first few apertures.
Bottom line
The Sigma 35mm f/1.4 DG HSM A1 is an impressive lens. Its combination of high-grade performance at wider apertures, excellent control of color aberrations and pleasing bokeh make it a winner.
The Sigma 35/1.4 does not need price to be compelling, but when one adds in the ridiculously low price of about $899 compared to about $1619 for the Nikon 35/1.4G, it might not only be the best lens here optically, but a striking value.
Long-term reliability and other factors were not evaluated here (though build quality seems excellent). But on an optical basis the Sigma 35/1.4 is surely a terrific buy.
