New ultra wide prime designs fare less common today than they were in the film era, and Nikon has had little need to do so since the introduction of the AF-S Nikkor 14-24mm f2.8G ED but there have been a couple of notable exceptions from third-party makers.
Zeiss introduced a Distagon T* 2,8/15 model for Nikon (and Canon) DSLRs and at $2,950 comes as little surprise to see it head this category. On the Nikon D610 the Zeiss even performs marginally better than on the Nikon D600.
|Carl Zeiss Distagon T* 2.8/15 ZF.2 Nikon||2950||26||16|
|Sigma 20mm F1.8 EX DG ASP RF Nikon||629||25||16|
|Carl Zeiss Distagon T 21mm f/2.8 ZF2 Nikon||1732||24||15|
|Samyang 14mm f/2.8 IF ED UMC Aspherical Nikon||409||24||19|
|Nikon AF Nikkor 20mm f/2.8D||570||24||15|
|Carl Zeiss Distagon T 18mm f/3.5 ZF2 Nikon||1395||21||13|
|Nikon AF Nikkor 14mm f/2.8D ED||1800||20||13|
|Sigma 14mm F2.8 EX Aspherical HSM Nikon||749||18||10|
Samyang’s 14mm f2.8 IF ED UMC is another excellent performer, and even its manual focus design doesn’t detract at this focal length. It has phenomenal central sharpness at full-aperture but it has stronger, more noticeable field curvature than the Zeiss though the performance across the field improves when stopped. Chromatic aberration is also rather high but at $409 the Samyang is a bargain.
The Zeiss Distagon T* 2,8/21 never fails to impress but at a third of the price, at $629, the Sigma 20mm f1.8 EX DG ASP RF is notable for its large aperture design and high image quality and excellent sharpness. It also has very low chromatic aberration, which is very unusual in high-speed wide-angle design like this.