Voigtlander 35mm nokton f1.4 ii MC forward focus wide open

[Derbyshire Man]

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Hi, anyone else got one of these? It front focusses wide open by about 1-1.25" resulting in quite a few missed close portraits. Spot on by f2.8. I can of course adjust if this is just the way the lens is but I had understood that the mk2 was designed to reduce the need for tweaks around focus. If you've got a copy what has been your experience?

Essentially I like the lens and am trying to get a feel during the return window whether it's worth rolling the dice again or just mitigating with me moving back at f1.4?

BTW the rangefinder is spot on, the nokton 50mm 1.2 perfect throughout it's range and the 35mm ASPH FLE also perfect although overshoots infinity (possibly hence why it was second hand!).

Cheers in advance!

[TomB_tx]

I have both ver 1 & 2 of this lens. With my various M cameras both are right-on at f1.4 and barely change by f2.0. The v1 would shift considerably beyond that, but the v2 is much better. The shift is noticeable in tests at 2.8-4, but beyond that the DOF covers it well. For my use I don't worry about the shift, as I don't notice it in actual use - just in testing with charts.

All my CV lenses have been had very accurate focus wide open.

[spydrxx]

My copy is spot on wide open but shifts after that thru f/4. You might have a technician adjust yours.

[sometimesmaybe]

3 hours ago, Derbyshire Man said:

It front focusses wide open by about 1-1.25" resulting in quite a few missed close portraits

the v2 shouldn't front focus, but try again (if you haven't done so already) with a static object and a tripod (not handhold). i find shooting at f1.4 at 0.7m there can be few variables e.g. my subject moving slightly, or me moving slightly or BOTH  

if it still front focuses, i'd ask for a replacement

[adan]

Spherical aberration (and thus focus shift) is simply a inherent function of the "old-school" non-ASPH double-gauss design, at larger apertures - but which permits the ultra-compact size.

For all practical purposes the Nokton 35 f1.4 is "1960s technology," just like the Leitz 35mm Summilux pre-ASPH it tries to emulate. 

See optical formula cut-away here: https://www.voigtlaender.de/lenses/vm/35-mm-11-4-nokton-classic/?lang=en

So there was not a lot that C/V could do to change that - outside of abandoning the whole idea and making a BIG lens with ASPHs (which they do in the f/1.2 and recent f/1.5 35 lenses). One cannot trifle with the laws of physics.

They do use one "abnormal dispersion" lens element (glass type, not glass shape/size) to improve things a bit - but mostly related to color fringing.

The focus cams on both my v.1 and v.2 were "factory-tuned" to be spot on at f/2.0, as the compromise location (shift one way at 1.4 and the other way at 2.8-4.0). Which was fine with me - I used it as an f/2.0 lens because f/1.4 was too dreamy, and if I didn't need f/2.0, I used f/5.6-8.

But the cam tuning be adjusted to user taste (spot-on at f/1.4, but more obvious back-focus at f/2-f/2.8) by a lens technician - although I have no idea where, outside of Japan.

Edited December 30, 2023 by adan

[hansvons]

2 hours ago, adan said:

The focus cams on both my v.1 and v.2 were "factory-tuned" to be spot on at f/2.0, as the compromise location (shift one way at 1.4 and the other way at 2.8-4.0). Which was fine with me - I used it as an f/2.0 lens because f/1.4 was too dreamy, and if I didn't need f/2.0, I used f/5.6-8.

I have the V2 SC version. I think of it as a budget Steel Rim. I find f 1.4 not working well on most close-up shots, as it's super dreamy with tons of halation and glowing going on in the highlights. Plus, the focus looks somewhat off, slightly shifted backwards. I have seen that with vintage Leica Summiluxes of the same Gauss design. But it's clearly spot on at f2 and again at f 5,6 upwards. 

The Nokton excels in its character and not with its high-speed capabilities of f 1,4. If you want a high-speed lens delivering good performance at full aperture, the ASPH Summiluxes are the way to go. You pay for what you get.

[Derbyshire Man]

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1 hour ago, hansvons said:

I have the V2 SC version. I think of it as a budget Steel Rim. I find f 1.4 not working well on most close-up shots, as it's super dreamy with tons of halation and glowing going on in the highlights. Plus, the focus looks somewhat off, slightly shifted backwards. I have seen that with vintage Leica Summiluxes of the same Gauss design. But it's clearly spot on at f2 and again at f 5,6 upwards. 

The Nokton excels in its character and not with its high-speed capabilities of f 1,4. If you want a high-speed lens delivering good performance at full aperture, the ASPH Summiluxes are the way to go. You pay for what you get.

Interesting information from all. Actually I do want soft and dreamy, but I want the subject in focus too, like the eyelashes rather than the end of the nose. With experimentation I can already account for it but wondered if this was a common theme. A couple of you have now said that f2 is spot on, for me it's f2.8 which is a smidge too far. I may well return this one and roll the dice again. The only problem is that stock seems in short supply.

And as I said in the original post, I have a Summilux 35mm 1.4 too, that is perfect in focus at close range at 1.4, it's not however perfect at the other end where it reaches infinity quite a bit before the final stop and indication on the barrel meaning you will get soft pictures if you trust it. With Leica I've been discovering you certainly don't always get what you pay for either!

[Harpomatic]

I think your rangefinder is off by a smidge:

I found Voigtlander lenses, bought used or new, tend to be just spot on, all of them.

I used probably 40 samples of them from screw mount from 2000 to brand new in the last 5-6 years. 
I had many, many Leica lenses and, if not for technicians threading them on the wrong thread on the helicoid after taking them apart, they tend to be spot on as well.

The rangefinder is a whole different matter: tiny calibration issues might let you focus some lenses almost perfectly and others completely wrongly.

Minor RF adjustments can make a big difference, and make all of your lenses focus perfectly.

I recently re-calibrated both my M10R and M10 that seemed absolutely ok till I had a lens that was off (a 1960s Tele-Elmar 135mm F4).

I recalibrated both cameras for it (tiny changes were required, although it front-focused quite a bit) and all my lenses got suddenly slightly sharper wide open!

Learn to calibrate your RF, it can make a huge difference! Your Summilux 35mm is proof that the RF is off.

Edited January 2, 2024 by Harpomatic

[sheedy]

I am having the same problem with this lens - Voigtlander Nokton 35mm 1.4 II.

I bought a used lens and tried it on my M9 and M240. On both cameras it front focussed by 40mm at 1.4 at closer distances <1m, so I returned it and bought a new lens. This one behaves exactly the same. I have other 1.4 lenses that focus spot on on both cameras with the same tests.

If I use live view on the M240, the focus is spot on, but switch to rangefinder and its off.

Is this a 'feature' of this lens? 

[TomB_tx]

I just re-tested focus with my M10 and 4 35mm lenses: The Voigtlander Nokton 35mm 1.4 II, the LLL 35 8 element, the VC Nokton 35 1.5, and my 35 Summarit 2.5 as a control.

I tested at 5 ft as a common working distance for me with 35mm, Focused each lens wide open from infinity to RF alignment (can be mechanical dead-band effects depending on direction of focusing movement) and repeated each 3 times. All 4 of these lenses were within about 2mm of perfect, with about that much repeatability with my eyes and technique. The Summarit showed maybe 2mm back focus though greater DOF at 2.5 makes harder to determine.

[lct]

No problem with my Nokton 35/1.4 SC v2 on M11 but there are sample variations so your copy may need some adjustment. I would check if your cameras are spot on too. If you see a difference between LV and RF the RF can be the culprit but you know this already i guess.