Description:

20mm f/4 non-AI Nikkor
20mm f/4 AI Nikkor


Suitable For:

General wide angle photography


Camera Formats:

FX and DX


Specs:

Focal length: 20mm
Maximum aperture: 4
Minimum aperture: 22
Angle of View: 94°
Focus throw: 140°
Maximum reproduction ratio: 1:11
Lens Elements: 11
Lens Groups: 8
Diaphragm Blades: ?
ED Glass Elements: 0
Autofocus: n/a
Minimum Focus Distance: 0.3m
Filter Size: 52mm Ø
Filter Type: front screw in
Dimensions: 63.5mmØ by 35.5mm
Weight: 210g
Accessories: HN-14 hood or HK-3 hood


Bjørn's Rørslett's Overview:

A petite lens replacing the big 20 mm f/3.5 (72 mm filter thread) from the Nikon F era, and also producing better pictorial results. Field curvature and corner coma could be bothersome for some applications of this lens, though. Needs to be stopped down a bit to give adequate corner sharpness - f/11 is a useful setting.
Some reviewers rank this lens much more favourable than this. I have no means of disproving or confirming their claims. It all boils down to how you, the end user, are satisfied with your particular sample. Remember the finite probability of sample variation.

I recently acquired a mint sample of the AI version and after adding a CPU, put it to use on DX (for IR) and FX cameras. On the D3 and D3X, I observed a good on-axis sharpness and very severe loss of quality into the corners for close subjects, while more remote scenes were rendered more evenly sharp across the frame. Still not what I'd call a peak performance, and the 14-24/2.8 Nikkor will blow the old-timer away.

IR: One reason I purchased this lens was a persistent rumour that the 20/4 had excellent IR capabilities. I partly agree, but it should be pointed out that flare in IR can be very troublesome even robbing the image of fine detail, and under some conditions the hot-spot issue rears its ugly head as well. So it is important to shade the front of the lens in an efficient manner when you do IR with it.


Bjørn's Rating:

3 (F5)
4 (FX: D3, D3X)
IR: 4-5 (DX: D200 (modified), Fuji S3 UVIR)


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