A bit of a lens comparison, inc. some Soviet lenses and focusing accuracy issues

[Coldkennels]

After picking up an M240 recently, I'd noticed a bit of weirdness with a pre-war Sonnar which I've used for years without issue on film, so I thought I'd do a quick focusing test in my office using a box of flashbulbs angled at 30-45º, positioned 1m away from the sensor, and I figured I'd also take the opportunity to do a bit of a PSA.

All lenses were focused on the I and the C in the magicube box with the rangefinder in the M240, *not* the live view, and are wide-open, unless otherwise noted.

Here's our baseline - a collapsible Summicron, recently totally overhauled by Skyllaney:


Perfectly sharp, nice rendering, focus is where I want it to be - the M in magicube is just dropping out of focus.

Next up, purely for comparison, is a (clean!) uncoated Summar:


Perfectly useable, nice and sharp, out of focus areas are a bit wilder and the colour is a bit less rich, but compares well with the Collapsicron.

And here's the 50/1.5 Sonnar at f/1.5 on an Amedeo adapter:


Noticeably a bit softer at all points - but also noticeably front-focusing, which I hadn't noticed on film. I could shim this for wide-open use, but it's close enough that I'm not that concerned.

 

[Coldkennels]

After looking at this, I thought I'd dig out a (very) late "Jupiter 8M" (big asterisk on that) in Kiev mount to see how it compares and check the adapter is accurate:


Focus is exactly where it should be. This is a really nice lens - it's actually in a Helios-103 style lens housing, which is rare. Upon cleaning it I found it seems to be a Helios-103 design inside, so I think this is a transition lens. Definitely a keeper.

But as has been discussed a few times in here over the years, unmodified Soviet "LTM" lenses back focus on a Leica, and I have a bunch lying around. Want to see how bad it is?


Hoooo boy. This backfocuses so badly you can actually start to get an idea of how messy my office is! This Jupiter 8 works perfectly fine on a Zorki - it's *not* defective. This is how post-war Soviet lenses were built.

Where things get really interesting, however, is this one:



This is a pre-war "FED 50", aka. an "Industar 10". It's a very close Elmar clone, and I bought it attached to a post-war Zorki. It never worked on the Zorki, so I put it on a shelf. Turns out this is because it's built to Leica spec - while there's a lot more depth of field at f/3.5, this is exactly bang on focus. Post-war 50/3.5 collapsible Industar lenses exhibit the same back-focusing of the Jupiter above.

So, for those who aren't aware, the history and the theory is this: Soviets copied the Leica directly before World War II. Early FEDs (like early Leicas) weren't standardised, but I have a feeling they were actively meeting Leica specification at some point before the war, if this FED 50 is to be believed. But after the war is over, the Soviets take the Contax designs and tooling, and every rangefinder lens and body made by the Soviet camera industry from that point on is built to the Contax specifications - even if they ostensibly have an LTM mount. The difference in what the two rangefinders took as the standard focal length (51.6mm for Leica, 52.4mm for Contax, if I remember right) is enough to cause real focusing issues.

You can see this yourself: if you set up a 1m "test bed" with any Leica and an unmodified Soviet "LTM" lens, the rangefinder can be in focus, but the focus scale on the lens will be closer to 1.1m. If you used live view, the lens would be in focus when set to 1m, but the rangefinder will appear way out. The issue seems to be how the lens interacts with the rangefinder, not the actual flange focal length. I'm sure @Sonnar Brian will correct me on that if I'm wrong.

So by taking the Kiev-mount version of those same lenses (the optics were basically interchangeable, from what I understand - it's probably the need for simplification and standardisation that led to the "LTM" ones being so far out from Leica spec) and putting them into an Amedeo adapter that is designed to interact with the Leica rangefinder correctly, you can actually use these Soviet lenses with accurate focusing.

I just wish I'd known that before I'd bought every Soviet lens in LTM mount all those years ago!

 

[DownUnder]

From a great deal of past experience, I am convinced that Soviet lenses and focusing accuracy are mutually exclusive.

I too had a large collection of those in my time. Acquired mostly from charity shops as they were so cheap. After using them, I realized why they had been given away to op shops.

Voiglander lenses, many now available secondhand at quite decent prices, are so so so much much much better.

Apology to the OP for my digression here. Something I felt I wanted to get off my chest...

 

[Sonnar Brian]

@Coldkennels
You are right! No mistakes here. The Inspection Sheets that I have for several Jupiters and Helios-103, and Menopta- show it is made to the Zeiss standard.

The Sonnar focus shift as you stop down is towards infinity. SO- optimize a Jupiter for close-up/wide-open, and stop down to F2.8 for infinity. The other factor; a 1% tolerance in focal length for the Jupiters. That means individual lenses on the Short-Side of the focal length are very close to the Leica standard. Twenty Years of cherry-picking lenses and shimming, mine are spot-on.

 

[oldhaven]

This is a really nice lens - it's actually in a Helios-103 style lens housing, which is rare. Upon cleaning it I found it seems to be a Helios-103 design inside, so I think this is a transition lens. Definitely a keeper.

I have one of these. The Ukrainian seller said this is a 1981 only lens made for the Bulgarian market. Does this sound right? I wonder if it is a transitional version to H-103 near the end of J-8 production. It appears to be brand new and I plan to try it on my best Kiev soon. Nice to hear of its good potential.

 

[Ko.Fe.]

I never bothered with Amedeo. Bit pricy and not as elegant and LTM to M.

I followed Brian's documents from old good times and asked at Russian Rangefinder forum.

As result I have ditched and see no reason to have any Leica 50mm anymore. I'm not a fan of 50ies.
I recalibrated early J3 and Canon 50 1.8 from Helen Hill. More than enough.
The focusing is incredibly smooth as well after my own CLA.
I had very sharp and funky colors O-15. Don't know why I sold it (well, not a 28mm fan either).
Got another O-15 while in Moscow. It is easy lens to calibrate.
And so are J-12. I had Soviet Biogon version now. Again, very impressive focus handling after my own CLA. And it is sharp, low distortions 35 with retro colors.
All are LTM.
I use focus test target scale to calibrate my lenses at approximately 45 degree angle , btw...

 

[Coldkennels]

From a great deal of past experience, I am convinced that Soviet lenses and focusing accuracy are mutually exclusive.

I too had a large collection of those in my time. Acquired mostly from charity shops as they were so cheap. After using them, I realized why they had been given away to op shops.

Voiglander lenses, many now available secondhand at quite decent prices, are so so so much much much better.

This is precisely the point I'm making with this post.

Soviet "LTM" lenses do focus accurately... on Soviet "LTM" bodies. This is by design and provable with a few basic tests. Or, alternatively, reading the spec sheet. They will not focus correctly on a Leica, Canon, Nicca, or Leotax without being shimmed.

Problem is that there's a lot out there that have been tinkered with in an attempt to make them work on a Leica. And for every Brian getting it right, there's a hundred people with butter knives doing it wrong.

Easiest solution is to pick up Kiev mount versions and use them on a Contax for perfect focusing - or, if you want to use a good camera, get an Amedeo adapter and use them on a Leica. Then they focus perfectly and can genuinely be incredibly good lenses considering their age. The Helios 103 is truly special, for instance.

Just skip the Soviet "LTM" ones unless you can either guarantee someone competent has adjusted them, you know how to do it yourself, or plan on using them on a FED or Zorki where they'll work perfectly fine.

 

[boojum]

This is precisely the point I'm making with this post.

Soviet "LTM" lenses do focus accurately... on Soviet "LTM" bodies. This is by design and provable with a few basic tests. Or, alternatively, reading the spec sheet. They will not focus correctly on a Leica, Canon, Nicca, or Leotax without being shimmed.

Problem is that there's a lot out there that have been tinkered with in an attempt to make them work on a Leica. And for every Brian getting it right, there's a hundred people with butter knives doing it wrong.

Easiest solution is to pick up Kiev mount versions and use them on a Contax for perfect focusing - or, if you want to use a good camera, get an Amedeo adapter and use them on a Leica. Then they focus perfectly and can genuinely be incredibly good lenses considering their age. The Helios 103 is truly special, for instance.

Just skip the Soviet "LTM" ones unless you can either guarantee someone competent has adjusted them, you know how to do it yourself, or plan on using them on a FED or Zorki where they'll work perfectly fine.

Yes, you are right. I have a few Jupiter LTM's. The 85mm is a little off and will get adjusted when I send it to Jadon. The rest have shown up shimmed for Leica and work fine. But they must be adjusted ff they have not already been. Other than that I have gotten good Jupiters. My '57 J8 is a real peach.

 

[Coldkennels]

I have one of these. The Ukrainian seller said this is a 1981 only lens made for the Bulgarian market. Does this sound right? I wonder if it is a transitional version to H-103 near the end of J-8 production. It appears to be brand new and I plan to try it on my best Kiev soon. Nice to hear of its good potential.

I believe this is correct based on the information on the Soviet Cams website. Mine came in a job lot of Soviet bits from an auction house and was raddled with fungus. Awful shape. Very easy to dismantle and clean, and no fungus remains. I thought it was a Jupiter 8M in a Helios housing - using up old optics in the housing made for the new lens - but mine definitely matches the Helios' near-symmetrical double-gauss design, not the Jupiter's asymmetrical Sonnar design. Works for me - the Helios 103 is the best lens the Soviets made, as far as I'm concerned.

Here's one from the Helios-in-disguise from a test roll after I finished cleaning it. These lenses are capable of good things when you're not dealing with the Soviet-to-LTM incompatibility...


("Jupiter 8M" via LTM Amedeo adapter, Leica IIIg, FP4+ in Rodinal)

 

[Coldkennels]

Yes, you are right. I have a few Jupiter LTM's. The 85mm is a little off and will get adjusted when I send it to Jadon.

From what I gather, the "LTM" Jupiter 9 (I really want to start calling these Soviet Thread Mount or STM, to be honest...) can never come fully into LTM spec - I'm sure I've seen @Sonnar Brian describing why somewhere. Again, you're almost certainly better off going Kiev-via-Amedeo on that one.

I actually have a Kiev mount one on the workbench that needs a strip-down and degreasing - it's so stiff that it keeps uncoupling itself from my Amedeo adapter. One for the next rainy Sunday...

 

[oldhaven]

Here's one from the Helios-in-disguise from a test roll after I finished cleaning it.

Very nice. Thank you. I look forward to trying mine, though without the adapter and on a Kiev. It sounds like it may just be a H-103 with Jupiter labeling, but I am not going to investigate unless I have problems. I see there are a couple more on the E auction site now.

 

[Sonnar Brian]

The later Black J-9 has a secondary shim for the rear group. About the best you can do- remove it to reduce the focal length, then reduce the main shim for focus. I got 1 good from minimum focus to about 20ft. A film-maker in Canada loved it, wanted it for portraits, sold it cheap to him. I like stuff that I hack getting used. A second one: early, no secondary shim. I purposely ground down an LTM to M adapter to bring it closer in. The error in the adapter and error in focus canceled, got good focus from 1.5m to infinity. RF agreement to ~30ft, then left myself some margin for infinity.

I think the J-9 focal length must be reduced to ~83.2mm or so, down from 84.5mm to be in good calibration with out this hack. Just too much grinding.


BUT- I much prefer using a Contax/Kiev J-9 on the cheap Chinese Adapters that I got for ~$65.

1955 Contax Mount J-9, LTM adapter.


One of the Best J-9s I've ever seen, my 1955 KMZ J-9. KMZ is the best. And for $65, shimmed it to match the adapter which SADLY is no longer made. The company cheapened the design, and it no longer can be used on external mount lenses.

 

[boojum]

I use the 85 rarely. My best bet would be on the M240 with the EVF. Or adapt it to another camera with visual focus rather than RF.

 

[Sonnar Brian]

From a write-up I did.

The problem: the focus mount of the Jupiter-9 translates focus for the 8.5cm focal length to the RF calibrated for 52.4mm. The “focus travel” of the RF cam calibrated for 52.4mm from minimum focus to infinity is longer than what is required for the Leica. The RF cam follower of the Leica gets pushed back too far, too quickly, and towards infinity. Reducing the focal length of the J-9 to 83.2mm would correct the error, but this required moving the rear group about 3mm. There is not enough room in the fixture to do this.



The Jupiter-9 requires an adapter for use on an M-Mount camera. The thickness of the adapter is critical in maintaining proper focus throughout range. If the mount is too thin, the RF cam pushes to far towards infinity. You need to focus the lens closer to get the RF to align. To quote Pinky and the Brain, “Are you thinking what I’m thinking!”: we have a lens that consistently back-focuses and an error that will make a lens consistently focus closer AND be able to reach infinity. Using an inexpensive Chinese LTM to M adapter that was slightly too thick to begin with, I polished it down “trial and error” fashion to bring the Jupiter-9 into good agreement with the Leica at closer range. I stopped at the point where the lens could be used from 1.3m to ~10m via the RF, and at infinity using the focus ring. The “best guess” was polishing the adapter down to 0.82mm thick, about 0.18mm thinner than the specification. Reducing the main shim of the lens by about 0.1mm was required to correct overshoot.

I wrote the package that generates these graphics over 35 years ago, all in Fortran. Paid for my 1990 T-Bird.

 

[Coldkennels]

I never bothered with Amedeo. Bit pricy and not as elegant and LTM to M.

I'd wanted one for years. Finding myself with a near-perfect uncoated 50/1.5 Zeiss Sonnar made it even more tempting, and when Amedeo made a batch of LTM adapters again, it was a no-brainer.

It's actually a pretty smart investment. There's a lot of "orphaned glass" in the Contax/Kiev mount that is a LOT cheaper than the LTM equivalents (whether we're talking Zeiss or Soviet), so once you get past the initial outlay, you're actually getting a lot of fun lenses to play with for much cheaper than you would otherwise.

That said, if you're not a 50mm fan, I get it. The 35mm-and-wider options in Contax/Kiev are slim, and the number of ones that are adaptable to Leica is even slimmer. Unless you also happen to own a Contax, buying an Amedeo adapter and a post-war Zeiss Biogon is a pretty daft proposal considering the amount of good 35mm lenses which are natively available in LTM or M mount.

But for 50mm? Like I said... no-brainer.

 

[GeorgeRazmadze]

Hello have you ever experienced using "Fotofox" Contax RF to L39 mount adapter? As I research it is rangefinder coupled only for 50mm focal lenght zeiss contax RF. Is it right?

 

[Sonnar Brian]

I have.

Inexpensive Chinese Contax Mount to LTM- Maybe a little work required.

EDITED: The design of this adapter has been changed and it can no longer be adjusted for external mount lenses. For internal Mount lenses- the adapter works correctly. I will be keeping my two "first-version" adapters. The newer ones- dedicated for an internal mount lens only. I have a total of...

www.rangefinderforum.com

The original version could be used with external mount Contax/Kiev lenses. The design was cheapened, and current version only works with 50mm lenses. It is best used with Nikon S-Mount 50mm lenses. Contax/Kiev lenses probably must be custom shimmed for it. I use the newer adapters for post-war West German Sonnars, easily adjusted.

 

[GeorgeRazmadze]

Thank you for your interest Mr. Brian. I have fed-2 soviet camera (M39 mount) and Zeiss opton sonnar 50mm 1.5 is there any otions to get any adapter which will have randeginder coupling?

(Why I want to use it on Fed-2? Because it is lightweight camera and designed as it gives you good feeling handling in hand and shooting)

Thank you for your time✨
Have a shiny day

 

[Sonnar Brian]

Thank you for your interest Mr. Brian. I have fed-2 soviet camera (M39 mount) and Zeiss opton sonnar 50mm 1.5 is there any otions to get any adapter which will have randeginder coupling?

(Why I want to use it on Fed-2? Because it is lightweight camera and designed as it gives you good feeling handling in hand and shooting)

Thank you for your time✨
Have a shiny day

George- I just checked this adapter with my Zorki-3M, and the RF Cam of the adapter is made to work with a Wheel type follower. It Jammed on my Zorki 3M. I do not have a Fed 2.

 

[Coldkennels]

George- I just checked this adapter with my Zorki-3M, and the RF Cam of the adapter is made to work with a Wheel type follower. It Jammed on my Zorki 3M. I do not have a Fed 2.

If it jammed on a Zorki 3M, it'll jam on a FED 2. It's exactly the same cam follower.

For what it's worth, my LTM Amedeo adapter mounts, focuses, and dismounts perfectly on my FED 2. It does seem absurd putting a £260 adapter on a £60 camera body, though!