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 p.1 #9 · Zeiss 21mm ZE vs. Nikon 14-24mm | |
Bobu wrote:
Today I tested my new Zeiss 21mm ZE against my Nikon 14-24mm. This was just a test of the sharpness of the lenses. Other aspects like CA, colors, flare etc. were not tested.
Understood. However the old 21 mm f/2.8 Distagon had much less lateral CA than the Nikkor 14-24 mm. I suspect the new one isn't quite as good as the original in that regard, though awfully close. Certainly better than the Nikkor zoom. It would be interesting to see a CA comparison.
Bobu wrote:
Summary:
The Zeiss 21mm has a much stronger vignetting until f/5.6 compared to the 14-24mm lens. The Zeiss has avery good sharpness between f/2.8 and f/8.0 (peak performance between f/4.0 and f/8.0). From f/11 the performance is reduced due diffraction (f/22 is very bad and in my opinion not useable at all). Between f/5.6 and f/16 the Nikon Zoom has nearly the same sharpness. At f/2.8 and f/4.0 the Zeiss is slightly better in the corners. At f/22 the Nikon is much better than the Zeiss (allthough the sharpness is also reduced at these apertures due to diffraction).
The effects of diffraction can't be avoided, so if one lens looks much better than another it's likely using a different f-stop. In this case your Nikon shot had a shutter speed of 1/13th while the Zeiss had 1/8th, yet the images are similarly bright. That suggests the Zeiss correctly stopped down to f/22, while the Nikkor did not, for whatever reason.
Thanks for the test, by the way. From what I've seen from these lenses, it's clear to me that the Zeiss is sharper in the centre and much shaper at the corners at f/2.8, but suffers from higher light fall-off at the edges (aggravated by today's digital sensors - see below). At f/5.6 the Zeiss is probably a fair bit sharper too, but the Nikkor is so good that we don't see a big difference on a 21-megapixel full-frame sensor. I would guess though, that the Distagon will leave the others trailing in its wake when we hit 50-megapixel sensors and beyond.
Pixel Perfect wrote:
Wow, the Zeiss also renders a much cooler image. That vigneting is pretty poor on the Zeiss. The Nikon is so good for a zoom it's hard to ignore. Canon Canon's possible offering (see the patent thread) match the Nikon? I bet they'll be using it as their benchmark.
The Zeiss isn't much cooler: the centre crops actually show the Zeiss being very slightly redder, with the Nikon greener. But the differences are tiny. The colour cast in the corner of the Zeiss image is down to the Canon 5D Mark II's sensor not coping well with non-perpendicular light rays (film doesn't have this problem, of course). The lens didn't project those colours.
I don't know enough about sensor design to know if we're likely to get rid of this problem in the future (maybe at the expense of sensitivity by redesigning or eliminating the micro-lenses). For now though, the Nikkor zoom obviously requires less post-processing (i.e. none) to get even colour rendition across the frame.
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What center distortion are you refering to?!
