Other/Uncategorized of Leica & FSU "standard"

Other Screw mount bodies/lenses

mike goldberg

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I seek clarity here from the guys who KNOW!

Earlier this year, I bought a J8 from Brian Sweeney, a superb lens collimated [modified] for my Bessa R. in other words, an FSU lens was converted, so to speak, with Brian's expertise for use on a Bessa R or Leica LTM camera body. That is called "Leica standard." Further, I learned that YOU DON'T PUT A "LEICA STANDARD" LENS ON AN FSU BODY.

The little tonge that protrudes at the top of the lens mount is different on FSU cameras. I understand the Russians did this to encourage the use of FSU glass :rolleyes:

I tried it... No harm done, but the negs were, well... as we say over here, "catastropha."

A logical question is, how about the other way round?!? Go to your favorite FSU Seller, and his economy lenses are advertised, "for Leica, M39, etc."

So, I'm wondering... are there clear cut answers for BOTH Leica standard and FSU standard?
Thanks, Mike
 
Hi Mike :)

This has often been a pretty controversial issue, but the basic case for the prosecution,made by Dante Stella here - http://www.dantestella.com/technical/compat.html - is that Soviet LTM lenses are derived from Zeiss originals and thus manufactured to a slightly different specification requiring adjustment for western LTM cameras.

I doubted this at first, but as I got more experienced I noticed that there did seem to be a fairly consistent difference. For example, mounted on a Leica 1 metre from a target, several I-61s routinely showed something like 1.08 - 1.10. As this suggests, any difference should only really be noticable at close focus with a fast or long lens, hence the fame of Brian Sweeney's J3s.

Others would argue that variations between individual lenses, in quality control or the difficulties of accurate close focusing etc. are in fact responsible for such results. Some Soviet lenses seem to function perfectly from the word go on classic Leicas, and at 2.8 or above simple DOF should eliminate problems with 35s and 50s. I also wonder if the focus shift which seems characteristic of some Zeiss lenses plays a part in all this, despite which I think the consensus is that there is a small but significant difference. There is also the seperate issue of rangefinder calibration and the fact that Soviet lenses were often adjusted to fit individual cameras, introducing yet another variable....

Incidentally, the relatively few Leica and Canon lenses which have a small tongue coupling will not fit FSU cameras due to the design of the Rangefinder cam, but most other lenses should - I have used CV lenses on Feds without difficulty and any FSU lens should fit a Leica or similar. I think the revised rangefinder cam on Soviet cameras was intended to simplify production as it requires a less precise manufacturing process than the Leitz roller.

Cheers, Ian
 
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mike goldberg said:
I understand the Russians did this to encourage the use of FSU glass :rolleyes:
They did that to streamline manufacturing, making same optical modules for lenses in Kiev and M39 mounts. Compatibility with Western gear was never an issue; I think only space aliens could care less about that than Gosplan of USSR.
 
Dante Stella's article has explained this issue.

However, "streamline manufacturing" may be not the reason of their choice. After all, they had two totally different camera systems. For "streamline manufacturing", they should have closed down one of them. :)

I guess that it maybe not so trivial to redesign a lens from 52.4 mm to 51.6 mm. A lot of computation could be included, and the glasses in Leica and Zeiss lenses could also be different. And it's possible that Russian only obtained the design of Zeiss lenses but no Leica's. So, they had to mount Zeiss-designed lenses on Leica-style bodies.

As to the "tonge", I think Russian designed it so that their cameras can be re-adjusted to fit Leica lenses, so it is a good design to improve compatibility.
 
The Jupiter-8 is not a very critical lens at f/2. If your negatives are consistently catastrophic, and you haven't been taking all of your photos at 1m distance and f/2 and taking advantage of whatever slim bit was left of the DOF scale at that distance, I wouldn't expect things to be that bad. Maybe there is another problem, such as the lens being mis-collimated anyway or, more likely, the camera's rangefinder being off?

Incidentally, on FSU cameras it is very easy to adjust close focus separately, by twisting the little angled cam follower on the rangefinder cam. So if you only use Leica standard lenses, you can adjust your FSU body to them without much trouble.
 
yek said:
However, "streamline manufacturing" may be not the reason of their choice. After all, they had two totally different camera systems. For "streamline manufacturing", they should have closed down one of them. :)
The Soviet Union was not without internal competition. This was everywhere: in the car world, you could choose between KamAZ and ZiL trucks, between a Zaporozhets and a Moskvich, in the plane world you had competition between Mikoyan-Gurevich and Sukhoi or between Tupolev and Myasishchev, and in the camera world you had, for example, some SLR makers choosing M42, others choosing Nikon bayonet. In a perfectly planned economy designed to be competition-free, this wouldn't have happened; there would have been only one model of everything. But the Soviet Union was no perfectly planned economy in this sense. When they started producing the Kiev, they already were producing a rangefinder camera in the FED, but the Contax was the best camera in the world, so it made sense to start producing it themselves once they had the chance.

yek said:
I guess that it maybe not so trivial to redesign a lens from 52.4 mm to 51.6 mm. A lot of computation could be included, and the glasses in Leica and Zeiss lenses could also be different. And it's possible that Russian only obtained the design of Zeiss lenses but no Leica's.
I don't think they obtained any Leica "designs" at all (they copied them anyway, FED-1). But they definitely had to recompute lenses, when they switched from using German-made lens elements to using their own glass; you never get the optical properties of glass exactly the same, and with different optical indices you need a new formula. At that point it would have been a trivial exercise to switch focal lengths. Also lenses were made by different manufacturers; since we do not know that all lens elements in the Soviet Union were made by the same company, there is really no reason to assume that a Kiev J-8M made by Arsenal should use an identical optical formula or basic focal length as a LTM J-8 made by ZOMZ or whoever, except a general assumption that planned economies are always very good at maximizing the efficiency of things (which we know not to be the case).

In fact people apparently rarely changed lenses. My wife didn't know that her FED-5 was an interchangeable-lens camera. Since every FSU camera can be adjusted to the lens' close focus distance, I wouldn't even be surprised if there are different versions of the same lens around - some J-8's may be built to standard A, some to standard B. The fact that the name is the same may not mean all that much.

Things being as they are, as a matter of fact, everything we know about whether they used Leica or Contax "standard" is conjecture, based on observation of lenses. For example, I tend to believe Brian Sweeney that there is a constructive difference between lenses, since he obtained this information by shimming and comparing. However, I would be careful to derive from this any systemic assumptions about individual technical design decisions in the various optical factories of the Soviet Union.

Philipp
 
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Based on the similarity between these Jupiters and Zeiss'es lenses, I guess they didn't re-compute them, at least in the first several years. Since they could get the design and machines for these lenses, they might also get the manufacturing technology and devices of the glass. ;) Or maybe they figured out how to make the glass by themselves. Then there was no difficulty to directly use Zeiss design. If they could compute and produce Leica focal-length lenses at that time, I believe they would do it, as they had done with the camera body.

As to the "cam follower", I agree with you that it is designed intentionally, so that these cameras can be adjusted to fit other lenses, such as Leica's.

Well, all of these are just my guess, based on what I have read here and there. I am too young to know these things by myself.
 
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Hi All,

I delight in the history in your posts above, along with the tech info. I read somewhere in a Google document, that in 1945, the trains from Dresden and Jena headed towards "Mother Russia," stretched for miles. They loaded up tools & dies and everything Zeiss and Contax they could carry.

As the post war Leica evolved and the market for M39 or LTM developed, chances are, the Russian/Ukranian lens industry adapted from Zeiss formulas. Chances?... Of course we know, for example, about the J3 based on the Sonnar design. My 50 year old Fed 50/3.5, a copy of the Leitz Elmar, is a winner.

In conclusion, it feels right to save me shekels for Leica & CV glass for my Leicas and Bessa R. On to dantestella...

Cheers, Mike
 
Question: Leica used a lens-to-film distance of 28.80mm. FSU cameras also use that measurement (bar a few very early examples). Ignoring the quality-control issues that we know existed, isn't is true to say that Leica and FSU lenses are the same, from a focus perspective? If not, will someone please explain why not. Lenses is not an area of expertise for me, by the way, I know only the basics.
 
mike goldberg said:
My 50 year old Fed 50/3.5, a copy of the Leitz Elmar, is a winner.
Cheers, Mike
My understanding from reading about this is that the FED/Industar 50 is *not* an Elmar copy optically, only cosmetically. I believe the iris is behind the first element on the Elmar, rather than the second in the FSU models. If it were a copy, they'd surely not have changed that? Not owning an Elmar, I'm open to be corrected on this, of course!
 
If to believe KMZ data, recomputation was done in 1954, when the stock of German glass was running out. USSR did produce its optical glass since early 30s, it was however not match in nomenclature and quality to Schott (and what in the world was). It did help the country to get through the war though, but afterwards the available German technology and expertise became accessible. So at that time Soviet optical science and manufacturing reached new heights.
 
Wolves
The FSU and the Leitz lenses will both be ok at infinity, because the nodal points of the optic with the slightly longer focus will be mechanically set further out by the difference in focal length.
If you wanted to focus 1:1 you need to move both lenses out by a different amount as they need to be 2x their focal length at 1:1. The same proportional difference is needed for further focus differences.
The FSU cameras and the leitz cameras had different focus cams, as the simpler lenses (in both) were used with one heliciod where the lens and cam moved the same distance for close focus, the engineer tweaked the cam in leitz lenses with a file!
Yes the Elmar and the Tessar are different, but in practice there is no performance issue, if each are optimised with similar refractive index glass.

Noel
 
Xmas said:
Wolves
The FSU and the Leitz lenses will both be ok at infinity, because the nodal points of the optic with the slightly longer focus will be mechanically set further out by the difference in focal length.
If you wanted to focus 1:1 you need to move both lenses out by a different amount as they need to be 2x their focal length at 1:1. The same proportional difference is needed for further focus differences.
The FSU cameras and the leitz cameras had different focus cams, as the simpler lenses (in both) were used with one heliciod where the lens and cam moved the same distance for close focus, the engineer tweaked the cam in leitz lenses with a file!
Yes the Elmar and the Tessar are different, but in practice there is no performance issue, if each are optimised with similar refractive index glass.

Noel
Ok, I follow that. So is it right to say that any lens will focus correctly according to its own scale, yet the RF might disagree with that scale? Presumably then this will apply to all FSU lenses versus Leitz? How much does it actually matter in reality? I'm asking because I'm looking at a IIIc body on which I'd planned to use FSU lenses!
 
I did some rough calculation before. ;) If I was not wrong, approximately, you can correctly focus further than 1 m for 50/2.8, 2 m for 50/2 and 3 m for 50/1.5.

Using FSU lens on Leica body, you can compensate the focus by multiply 0.97. When the rangefinder shows focus correct, read the number on lens scale, multiply it with 0.97, and re-focus to that number. If the compensation amount falls within DoF, re-focus is unnessesary.

For example, if lens scale shows 1 m, then rotate the focus ring to 0.97 (if possible). If it shows 2 m, then change to 1.94. If it shows 3 m, then change to 2.91, etc..

Here, 0.97 is from (51.6*51.6)/(52.4*52.4).

Just calculation, no experiment yet. So I may be wrong. :)
 
yek said:
I did some rough calculation before. ;) If I was not wrong, approximately, you can correctly focus further than 1 m for 50/2.8, 2 m for 50/2 and 3 m for 50/1.5.

Using FSU lens on Leica body, you can compensate the focus by multiply 0.97. When the rangefinder shows focus correct, read the number on lens scale, multiply it with 0.97, and re-focus to that number. If the compensation amount falls within DoF, re-focus is unnessesary.

For example, if lens scale shows 1 m, then rotate the focus ring to 0.97 (if possible). If it shows 2 m, then change to 1.94. If it shows 3 m, then change to 2.91, etc..

Here, 0.97 is from (51.6*51.6)/(52.4*52.4).

Just calculation, no experiment yet. So I may be wrong. :)


Hi everybody.
Made this experiment. With Leica M3 and 2 Jupiters 8, with M39 to M-mount adapter. Roughly put, on 1 meter f2 when in focus on RF, the lens ring says about 105 cm. And that's where the true focus is. But when you close the lens for two stops, I really cannot tell that the focus is off. I chose to ignore it, instead of messing with it. Guess I'm lazy.
I suppose that it works the other way around, with e.g. Elmar on FSU body. However, i can't try that, my Elmar and Summicron have M-mount, no 39mm.
 
Use FSU glass on your leica if you want to. Some lenses display the shift, others do not; you won't know how yours behaves until you try it. Even if your lens has the shift, you probably won't notice the problem unless you do a lot of portraits at f/2 and 1 or 2 meters. If that's your style, you might have a concern. "Focus on the nose, not the eyes" seems to work pretty well in that situation.

I've been using FSU lenses (J-3, J-8, J-9, J-11, I-61LD) on my Bessa R for two years now, and I've never been unhappy with the results. Admittedly, I mostly shoot outdoor daylight stuff, so I probably wouldn't know if my J-3 is back focusing by 2.5cm at 1m at f/2 or wider. I'm very very happy with all of these lenses.
 
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Thank you for doing the experiment! It looks quite close to the calculation result. I thought this experiment should be difficult to do because FSU lenses often have quality issues which can affect the test result. So your Jupiters must be very precisely built. :)

So, the quality issue of FSU lenses may be not so serious as often said to be. They just have a different standard.

Thanks again!

:)
 
It was my pleasure.
When my Leica arived, i realised that original lenses are ruined, and after reading Mr. Dante's review, I was afraid that my M body will be useless (or will have to spend a few hundred $ for a good summicron or elmar).
Now I see that is not so bad.
OK, I won't be using a lot 25 ASA films...so what? :)
 
My jupiter 8 focuses perfectly on both my Bessa-R and Fed-2.
And I shoot wide open and close range (read: short DoF) a lot.
 
Interesting...a few weeks ago I bought a Zorki 4K with a black Industar 50 f3,5..a particulary ugly lens. tried it on same Leica with M adapter..focuses pefectly!! tried with a focusing screen on 1,3,5 m and infinity. Must have been shimmed for Leica by someone in the past..because it is off by the same 5 cm on both Zorkis..;) Now..if only it wasn't so ugly looking....:(
 
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