Lens focus adjustment - options?

[LocalHero1953]

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I have an old Nikkor 10.5 f/2.5 on an M39 mount that I fit on my M240 with a Voigtlander adapter. The focus is off at close range (distance is not too bad, but I'm only likely to use it at close range). At closest focus of 4 feet, it back-focuses more than 5cm. (My M is OK with other lenses, so it is likely the Nikkor at fault).

 

What are my options for getting it adjusted more accurately? I've looked at the LUF recommended repair specialists for the UK, and CRR is not accepting any repairs till the summer, Protech appear to deal only with IR conversions, and the other two appear to have a declining reputation for turnaround and responsiveness.

 

Firstly, is there anyone else out there who could do what should be a straightforward task?

Secondly, is this something a reasonably handy sort of guy like me could attempt? Does it need specialised calibration tools, or is it a trial and error thing? If so, can anyone point me towards resources (service guides etc) that would help?

[Guest JonathanP]

I used Will van Manen recently to bring a Hexanon 90mm into spec for use on my M240. Turn around was very good (I think it was only at his for less than a week, much better than any of the UK options that I know about). Downside is the cost of postage each way and bank transfer fees means you can double the basic cost of a CLA. Would be good to find such a good service in the UK - Cathy & Will respond to emails and provided a very professional service.

 

Jonathan

[Erik Gunst Lund]

It is a unit focusing lens (no internal or floating elements) so it will be off at all distances, not just close up.

 

The lens doesn't have a roller on the cam follower so it slides along the surface...

The 135mm Tele Elmar has an roller for instance.

 

So the Nikkor cam will wear over time, mine was very worn when I got it it, also the whole cam follower was a little loose... A repair shop can fix it for you.

[hoppyman]

I don't understand how you are operating with this lens? isn't the Livewiew is only focus option you have for any adapted lens?

[LocalHero1953]

I don't understand how you are operating with this lens? isn't the Livewiew is only focus option you have for any adapted lens?

 

This version of the lens was designed for the Leica screw mount and rangefinder, so with the M39 to M adapter it also operates the M240 rangefinder cam. The Voigtlander adapter is the version that brings up the 90mm frame lines. This is good enough at the moment for estimating the 10.5cm frame (allowing for the inaccuracies of the M frames anyway ).

 

And yes, I could use the EVF if I had one - I'm trying to get by without one at present.

I used LV on the rear screen to test the focusing accuracy.

[hoppyman]

Aah, interesting , thanks. I never handled an adapter nor this lens.

[LocalHero1953]

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It is a unit focusing lens (no internal or floating elements) so it will be off at all distances, not just close up.

 

The lens doesn't have a roller on the cam follower so it slides along the surface...

The 135mm Tele Elmar has an roller for instance.

 

So the Nikkor cam will wear over time, mine was very worn when I got it it, also the whole cam follower was a little loose... A repair shop can fix it for you.

 

From some quick calculations, a half millimetre wear in the cam would cause about 5cm back-focusing. So I could try a quick fix using some aluminium foil as a shim on the lens-adapter interface. Nothing to lose.

[menos I M6]

Paul, first off congrats on the lens. This lens is famed for a reason - it was back then a landmark lens, peaking in performance other manufacturers lenses in this range in quality (including Leitz offerings).

 

Whatever you do with this lens, make sure, it is done professionally, preserving this lens.

Even by 2014 standards it is still a very, very respectable lens.

 

Your lens does have an easily removable optical cell, which comes right off twisting the lens head CCW.

 

Between the optical cell and focussing module should be a shim - sometimes the factory shim is lost over the years, resulting in lenses, significantly back focussing.

This is an easy fix for a reasonably handy person, best by a repair person, who can also check on the other areas, these lenses like to develop issues (mostly with these Nikkors a needed CLA to the aperture control mechanism, as old grease dried and makes the control ring uneven/ sticky, uneven/ sticky focussing feel and potentially oily aperture blades which might or might not need attention).

 

Inspect your lens' cosmetics - should it be in mint cosmetics, wear to the RF cam follow mechanism is unlikely but a fresh cleaning and lubing of these areas with proper materials is likely on tab, should it not have been done over the last ~10 years.

 

Additionally, please understand that this is in fact a Sonnar lens design, which will always display a certain amount of focus shift.

You can either calibrate it for wide open use close up or further away by shimming the optical cell to the focus module.

I prefer mine to be set up for wide open close up use and simply stop it down for far away distances.

 

Again, it's a great lens - keep it in good working order and use it!

 

A small tip - Nikon also designed a close relative to the 10.5cm Sonnar - the 8.5cm f1.5 Sonnar, issued in a very similar mechanical construction but very different optical character. Once you like your 105/2.5, chances are you can easily fall in love with the 85/1.5 LTM ;-)

[LocalHero1953]

A small tip - Nikon also designed a close relative to the 10.5cm Sonnar - the 8.5cm f1.5 Sonnar, issued in a very similar mechanical construction but very different optical character. Once you like your 105/2.5, chances are you can easily fall in love with the 85/1.5 LTM ;-)

 

Thanks for the advice and information, Dirk. I agree with you about the quality of this lens. An early shot with it is in post #1892 here:

http://www.l-camera-forum.com/leica-forum/leica-m-lenses/253049-view-through-older-glass-95.html#post2647092

 

The focusing action is a bit stiff and uneven, so I guess it will go for CLA before long, even if I'm able to fix the focusing error temporarily myself. I would also want it set up to focus at close range.

 

I am trying to find a set of older, softer portrait lenses to match my painfully sharp modern Summicrons. This is my first foray into the field. I'm interested in what you say about the Nikkor 8.5/1.5; based on the advice on the Cameraquest website (Leica Screw Mount Lenses) I was looking for a Nikkor 8.5/2 or a Canon 8.5/1.8 in LTM mounts. How does the Nikkor 8.5/1.5 compare in character to those and the Nikkor 10.5/2.5?

 

PS I'm also looking for a Hektor 7.3!

[Erik Gunst Lund]

..., wear to the RF cam follow mechanism is unlikely...

 

As I stated above, the RF cam follow mechanism lacks a roller, it's a solid screw head sliding on the surface, so it will slowly but sure wear itself and since the lens is about 60 years old... there will be a flat spot and it will wear more in the beginning then less and less...

 

Anyway congratulations with the lens, it has a lovely rendering. I love mine I also have it in Nikon F mount. solid performer also for IR.

[menos I M6]

As I stated above, the RF cam follow mechanism lacks a roller, it's a solid screw head sliding on the surface, so it will slowly but sure wear itself and since the lens is about 60 years old... there will be a flat spot and it will wear more in the beginning then less and less...

 

Anyway congratulations with the lens, it has a lovely rendering. I love mine I also have it in Nikon F mount. solid performer also for IR.

 

Erik, here would be the complete quote, not taking things out of perspective:

 

Inspect your lens' cosmetics - should it be in mint cosmetics, wear to the RF cam follow mechanism is unlikely but a fresh cleaning and lubing of these areas with proper materials is likely on tab, should it not have been done over the last ~10 years.

 

Thank you.

 

 

I am trying to find a set of older, softer portrait lenses to match my painfully sharp modern Summicrons.

This will be difficult with the older lenses from Nikon and Canon, as these have generally a lot less contrast.

Matching modern Leica lenses with the wish for a softer rendering, you could have a look into lenses produced in the 70s or 80s.

The best (but probably also most pricey) example for this would be the 75 Summilux which can be matched very well with modern, contrasty, sharp Leica lenses.

 

With the older lenses to fit well into a set with modern, sharp lenses a bit of post processing, adjusting the black point, contrast and possibly curves often does the trick though while retaining the lovely rendering of the older lenses.

 

I'm interested in what you say about the Nikkor 8.5/1.5; based on the advice on the Cameraquest website (Leica Screw Mount Lenses) I was looking for a Nikkor 8.5/2 or a Canon 8.5/1.8 in LTM mounts.

 

The Nikkor 85/1.5 LTM is for Nikon RF aficionados something like the 75 Summilux is for Leica M users.

It is nowadays mostly a collectible lens as of it's rarity (only a few hundred were ever produced in LTM mount).

 

It compares very well stopped down to f2 with it's slower little brother the Nikkor 85/2, which for good reason has been one of the lenses, bringing Nikon worldwide fame during the 1950's.

I would go so far to state, that reason to buy the 85/1.5 over the 85/2 is exclusively for the magic that happens at wide open aperture of the f1.5 lens.

The 85/2 is in my opinion the greatest performing vintage short telephoto for the money with f2 aperture. It is a fantastic lens, but with its all massive brass construction surprisingly heavy for it's compact size.

 

The Canon 85/1.8 LTM (latest all black aluminium lens, not the older all chrome, heavy brass version) is probably the highest performing 85/2 of the era (it was the latest introduced to the market of these vintage short telephoto lenses).

It is a wonderful lens, relatively compact and lightweight (all aluminium barrel, except it's brass helicoid).

It is a shorter modification of the equally impressive Canon 100/2 LTM, which is my favourite lens of the fast Japanese short telephoto lenses.

 

The Canon 85/1.8 is the most rare to find of these, closely followed by the 100/2 LTM, while the 85/2 Nikkor LTM can be found easily also at the most affordable prices among these.

 

How does the Nikkor 8.5/1.5 compare in character to those and the Nikkor 10.5/2.5?

 

In my opinion the Nikkor 85/1.5 is the very only ~85mm lens, which can come close in beautifully smooth rendering to the original Carl Zeiss Jena 85/2 Sonnar.

 

During the same era several makers were in a heated race for the fastest lenses - notable directly comparable entries were the older Leitz 85/1.5 Summarex and the Canon 85/1.5 both of which are easily eclipsed in performance by the Nikkor (higher resolution + smoother out of focus rendering).

 

The Nikkor 85 lenses draw in my opinion entirely different to the 105/2.5 Nikkor, which has a more modern look with higher contrast, higher resolution and a more even field.

I prefer from all of these the Canon 100/2, which seems the most versatile with fast aperture, yet lightweight barrel and good reach at 100mm.

 

PS I'm also looking for a Hektor 7.3!

 

The 73/1.9 Hektor is an entirely different beast to the much later designed Japanese fast portrait lenses.

It serves to produce a very distinct soft, low contrast look, dreamy with low resolution and very low contrast.

 

It is a rather expensive lens now for what it is and for how it compares to later vintage portrait lenses as it has become collectible as of it's age, if in well preserved optical condition.

 

The sample I have has lost part of its antireflective lens element paint and has slight haze, serving to create a very special look, no photoshop action can produce ;-)

 

Here is the 73/1.9 Hektor wide open:

Hektor 7.3cm ƒ1.9 *1932 by teknopunk.com, on Flickr

 

Here is the Nikkor 85/1.5 LTM wide open:

Shanghai | wet market - customer by teknopunk.com, on Flickr

 

Here is the Nikkor 85/1.5 LTM stopped down to f2 which looks almost indistinguishable with a Nikkor 85/2 - in my opinion the best fast vintage portrait lens to buy for the money:

portrait - JC - table by teknopunk.com, on Flickr

[LocalHero1953]

Thank you, Dirk, for as comprehensive a survey as I've been able to find.

I should have been more accurate in stating my intentions - I want to find older lenses that complement (not match) the sharpness and contrast of my modern Summicrons. So softness and lower contrast are OK for me.

Nikkor 85/2s seem to be readily available in N America, but I'd like to find one in Europe and avoid customs and VAT problems. Hectors are readily available in Europe, but at a price, as you say. The others you discuss are scarcer. I shall have to be patient.