Three wide angle lenses compared on D800e
In searching for the best possible wide angle lens to use on Nikon's D800e, I compared three lenses, the Nikon 20mm f/4 Ai, Nikon 14-24 f/2.8, and Zeiss 21mm f/2.8. While they are not the only lenses that would fit my needs (that is, 84" prints), they are the ones that were first available to me. Various sources online also indicate Nikon's new 16-35 f/4 would also do well, however it was not tested. Nikon's newest 20mm f/2.8D seems to fall somewhere below those, and generally unimpressive on the D800, however it too was not tested. lensrentals.com has a page about other lenses and how they tested in terms of MTF on this page.
The images were shot as 14-bit .nef, imported into PS5 with no adjustments, and processed as full quality ('12' in PS) sRGB 8-bit JPG for internet use. All images were shot on a tripod using a cable release; mirror lockup was not used. Exposure was f/5.6, 1/640, and ISO 100.
Nikon 20mm f/2.8 Ai
This is quite an old lens, however it is very light. When used with the D700, it performed well with some noticeable loss of sharpness and contrast on the far right of the frame and in all corners. On the D800e its shortcomings that were always present become more obvious. Loss of contrast, quite blurry, unacceptable for large prints. Here is a 100% crop from the upper right:
Nikon 14-24mm f/2.8 AF-S N
Only a few years old, featuring Nikon's Nano glass and designed for their FX digital bodies. A world of difference from the 20mm Ai, little vignetting, great contrast and sharpness, very little loss of either in the corner. This image was shot at 20mm; expect corner results to be worse at 14mm.
Zeiss 21mm f/2.8 Distagon T*
Better than the 14-24mm in every way. Better contrast, better sharpness, less falloff (though only slightly so) at the edge. For my purposes, also smaller and lighter.
The Zeiss, to my eyes, certainly seems to have superior image quality and a greater ability to exploit the D800e's sensor.
It's interesting to note what while all three images were shot at f/5.6, 1/640, and ISO 100, the older Ai resulted in a slight underexposure and the other two lenses metered the same; the scene was metered originally with the Zeiss.
The Zeiss is slightly cheaper than the 14-24, performs better, is lighter, and smaller. The 14-24 may be found used for cheaper, however, while finding the Zeiss used is more difficult. I have no need for the zoom and need every bit of image quality possible, so I chose the Zeiss.