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Explore the world of vintage lenses through repair notes, real test shots, and detailed forum threads packed with images.

Explore the world of vintage lenses through repair notes, real test shots, and detailed forum threads packed with images.

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Carl Zeiss Jena Flektogon 20mm f/4 Lens Review

09/09/2006
Carl Zeiss Jena Flektogon 4/20mm “Zebra” lens one of the Carl Zeiss Jena legend. A very few people know it for architectural photography you can’t find better lens even if we compare the very expensive Carl Zeiss Distagon lenses. This lens has zero distortion I say this is the must have lens for serious photographers. Mechanically not very well built, but far better than today’s plastic craps. This lens has no auto-manual switch or pre-set ring,it has a push button to set the lens in manual mode. Under exposition if you use on digital camera with an adapter ring you must have push this button to close aperture to the right position.On film cameras the auto mechanism works perfect don’t need to push.Almost all people think about the latest MC version and less people pay much attention to this lens, this is a big mistake this lens better lens than latest black MC.If you have a chance to grab them take them both and if you disagree with me just sell one of them. As usual these lenses not wait to much time for selling.

Lens


Related resources

Lens Schema


Flektogon 4/20 Schema

Fact Sheet


Vendor name
Carl Zeiss Jena
Type
Flektogon
Product year
N/A

Focal Min(mm)
20
Focal Max(mm)
20
Focus Min(cm)
16

Aperture Max
4
Aperture Min.
22
Barrel length(mm)
59

Elements In Group
10 in 6
Diaphragm action
auto|manual
Weight (g)
320

Filter Size (mm)
77
Push on diameter (mm)
80
Angular field
93

3 Comments

  1. Regarding the Flek 4/20’s lack of distortion, I can only echo Orio’s comments – it’s pretty much unbeatable for architecture. The mighty Distagon 21 has “moustache” distortion and this makes it a bit more difficult to straighten out and because of this, any “adjustment” will almost certainly impact on it’s IQ.

  2. If you want a sharp 20mm lens, buy a Nikkor. The Fleks have sufficient sharpness for most use, but if sharpness is critical, I would choose another lens. As for compared to each other, well, both of them are soft wide open. I feel that the 4/20 gets sharper faster, as it’s useable already at 5.6 (note I said “useable”, not “good”), while the 2.8/20 seems to take more (it also becomes useable at 5.6). I am of the impression that compared to the 4/20 the 2.8/20 may be some sharper in the centre, but for sure, it is weaker in the corners. While I would not mind too much corner performance on a portrait lens, for the way I see the super wide angle photography, I prefer a more uniform rendition.

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