Nippon Kogaku Nikkor-O 2,1cm/4.0

[chris dees]

I wanted to buy this lens for use on my Z with the FTZ-adapter. Problem is, it doesn't fit on the FTZ.
According to Roland Vinke's website it's a very early model (1959/60).
The seller said the thickness of the F-mount has changed and newer models would fit.
I don't quite understand this because I have other lenses from that era that fit (5.8/1.4 and 13.5/3.5 both fro 1959 or so).

Is there a way to make it fit on an FTZ?

[richardHaw]

i think that one has a long skirt, youll have to find a cheap chinese adapter and machine it or find an older adapter from the F2 era and adapt it to a leica adapter then adapt it back to Z

even if you managed to get it to mount if i am not mistaken then rear element will hit something it goes deep

[Erik Lund]

https://nikongear.net/revival/index.php?topic=7705.msg127173#msg127173
 http://nikongear.net/revival/index.php/topic,5290.msg83795.html#msg83795
To start off with 

[chris dees]

I'm familiar with the strong warnings of Birna, the lens is not ment for a DSLR.
The lens is not too long for the FTZ (only 1-2 mm) and will not touch the sensor.

Could a K1-ring help?

[richardHaw]

the ring will help

its not the sensor thats in danger but the shutter i was told...clearance is very slim so be careful with your adapters.

now, i do remember mr Goto once warning us over dinner that the 2.1cm will work with a nikon Df when you lift the mirror manually BUT it still actuates and he showed us that there should be a mark where the mirror hits the lens tube and there really is one

[Birna Rørslett]

I'm familiar with the strong warnings of Birna, the lens is not ment for a DSLR.
The lens is not too long for the FTZ (only 1-2 mm) and will not touch the sensor.

Could a K1-ring help?

The K-1 would throw focus way off. No hope of seeing infinity.

It *is* possible to use the 2.1cm lens on a Z camera if you juggle around with adapters. However it is hardly worth the bother except for satisfying the urge to use an ancient lens on a modern camera Focusing is very awkward and near limit is around 0.9m, which makes the lens almost useless in practice. Image quality is so-so, nothing to write home about. The Voigtländer 21mm f/4 lens is more compact, much easier to focus, and can be had for a lesser price as well. I mount it via my Nikon(RF)-Z adapter. While the Voigtländer also stops at 0.9m, it has a better image quality.

Best of these wide and still quite easily available RF lenses is the Voigtländer 25mm f/4. My definitive favourite. It is downright cute on any Z camera and delivers very good image quality, a quality which also extends into the IR range.

Nikon modified the 2.1cm to make it possible to use on the early Nikkormats. The first version of the 2.1cm had too massive rear flange. Never ever use the 2.1cm on other than Nikon F, F2, and the early Nikkormat. You will destroy the mirror of your SLR/DSLR.

Chris, the serial no. of my 2.1cm Nikkor is less than 100 units away from your lens

[chris dees]

Thank you all. Not worth the hassle. I'll let the seller know I'll pass.

[Roland Vink]

Early models have a wider lens mounting grip - the metal knurled ring around the lens mount. The grip extends below the surface of the lens mount and can prevent the lens fitting to some cameras and adapters. I guess this is what prevents it fitting the FTZ.

Lenses with serial no 225001 and higher have a narrower mounting grip which extends less below the lens mount, giving more clearance so it could fit early Nikkormat cameras, and probably also the FTZ.

[Bill De Jager]

Nikon modified the 2.1cm to make it possible to use on the early Nikkormats. The first version of the 2.1cm had too massive rear flange. Never ever use the 2.1cm on other than Nikon F, F2, and the early Nikkormat. You will destroy the mirror of your SLR/DSLR.

Chris, the serial no. of my 2.1cm Nikkor is less than 100 units away from your lens

Mine is also fairly close, just a little bit older. I was unable to mount it to mirrorless cameras via adapters because they just wouldn't fit the lens.  Now I know why.

[mxbianco]

Early models have a wider lens mounting grip - the metal knurled ring around the lens mount. The grip extends below the surface of the lens mount and can prevent the lens fitting to some cameras and adapters. I guess this is what prevents it fitting the FTZ.

Lenses with serial no 225001 and higher have a narrower mounting grip which extends less below the lens mount, giving more clearance so it could fit early Nikkormat cameras, and probably also the FTZ.

My sample (1967), with serial no. 226xxx is a possible candidate for testing. After this morning's stroll up the hills, I will see if the 2.1cm and FTZ will cooperate...

Good thing about FTZ is that you don't compromise the camera until the last moment, and it's easy to see if it clears the FTZ's bayonet mount.
Another possible problem is the shorting of the FTZ contacts by the  non-standard mount of the 2.1 cm... Beware!

Ciao from Massimo

[Birna Rørslett]

I just did a quick test comparison betwewen 2.1cm f/4 Nikkor and the Voigtländer 21mm f/4 Skopar, both mounted on a standard Z6. On axis they are not very dissimilar, however the Nikkor renders the corners very smeared with great loss of detail. It is also hampered by the rear element being so close to the sensor surface thus there are lots of colour vignetting of the cyan kind.

My advice, don't bother with this lens. I have fond memories of it in conjunction with film and a DIY adapter for the Nikon S3, a combination which delivered some great shots in the forever gone film era. I cling to this  impression and use something else on my Z camera

[Birna Rørslett]

If the previous post wasn't decisive enough, here is the direct corner comparison between the Voigtländer 21/4 (left) and 2.1cm f/4 Nikkor (right). Both lenses at f/8. The crop is 100% and is straight off the Z6 NEF through Photo Ninja with default settings.

[chris dees]

I just did a quick test comparison between 2.1cm f/4 Nikkor and the Voigtländer 21mm f/4 Skopar, both mounted on a standard Z6.....

How did you mount the Nikkor on your Z6? A DIY adapter?

[paul hofseth]

ad mounting: ages ago I used a combination of Novofles Nikon mount and a Leitz threadmount extension ring with araldite to mount the 21/4 to my Leica. On Kodachome II it worked , despite my ignorance of wide angle dependence on exact distance to film plane. Remembering toscrew in the adapte before mounting the lens and observing the right twisting when mounting was essential. I trust that my former 21 stli has marks on the rear element protctive  shield due to my mistakes.

The viewfinder suffered a mishap so I wrote Nikon to source a new rear VF element, but they replied that they did not keep so old spares, something that put me off Nikon in favour of Leitz for years, but by now Leitz no longer provides service for some of their old equipment.So I have abandoned them in favour of Nikon even though I do not expect any difference in longevity

p. 

[Birna Rørslett]

I might have got the lens from you, Paul.

Chris: I did cobble together a DIY adapter Nikon F-RF(S) in the old days to use the lens on my black Nikon S3. When I purchased some Cosina-made Voigtländer Skopars for the RF mount some years ago, I also got a factory Cosina/Voigtländer F-RF(S) adapter from S.Grimes.  No problem for any of the two solutions to mount the 2.1cm Nikkor despite it being of the early generation.

To mount the 2.1cm on my Z bodies, I used a K&F Concept Nikon RF(S)-Z adapter together with the CV adapter.