Fed lens working distances

[Valkir1987]

Dear Enthusiasts,

I recently got two Fed 1F body's without a lens. I already had an F type with a lens. I tried and measured out some things, and came to the following conclusions.

-all the checked F models, with the serial numbers: 232966, 285221, and 285969 have the same lens pitch thread. Which is different from the Leitz one.

-their lens to film flange distances measured out 28,44 mm on the three camera's.

-there are no major differences in their design, engraving, finish or built quality. One needs a CLA and curtains, but the quality is very good.

What kind post war uncoated Fed lenses and accesories where produced to work with these models? Except the regular Fed 3,5/50
The 6,3/100 comes into mind, but I thought they where only produced before the war.

With kind regards,


Valkir

 

[David Hughes]

I don't want to start the replies by disagreeing but my experience is that the FED 1f's, 1g's and 2's have the same thread as the Leica I's, II's, & III's (that's IIIa to IIIc); Elmars, Summars and Summitars. That means my Leicas from 1932 to 1949 and FED/Zorkis around 1950 to '53. Mostly industar 10's (early and FED 2 version), a 22 and a 50; plus a Jupiter-8 or two.

What is noticeable is that the infinity lock ends up all over the place. It's best, imo, to keep each lens for its specific body. That hasn't stopped me from using any lens on any body including the CL and M's with an adapter.

There was one exception, a 1932 Elmar; it fitted the FED's but not the Leicas! Eventually Malcolm Taylor told me that a lot of people cleaned Leica thread and assumed they were 1mm pitch but they are 0·75mm pitch. He also mentioned that there's a hybrid version used.

BTW, surely 1f's only came with coated lenses?

I don't think we'll ever get to the bottom of all this without a complete set of engineering drawings from all the factories and then a year or two checking cameras against the drawings and trying to eliminate the varieties introduced by kitchen table repairers and those naughty exporters in the former USSR, who will marry any lens to any body if it looks right and might sell. You might say the same about Leicas...

Regards, David

 

[Valkir1987]

Dear David,

I don't feel you disagree with me, because I had the same experience. What you told about the 1932 Elmar is interesting. I know few about the standardization of the Leica mount tread pitch.

As far as I know, the F's came with uncoated lenses, later ones came with coated lenses and a new aperture scale. Later F's and G's are Leica compatible.

On the prewar NKVD body's I have the infinity locks at random. I alway's keep the original lens with its body it came with. But in some cases there is only a body, and finding a matching lens with a corresponding focus is difficult. Unless you borrow a different mount and collimate the camera's working distance to 28.8 mm, and use different optics.

I am convinced that the three 1F examples I speak of are genuine, no parts have been mixed up afterwards. The fact that they are from the same production range, sharing the same pitch thread and lens working distance. Show that they where standardized (to a different standard), but for what purpose I am stil wondering.

Maybe one should dig up his or hers 1F with an uncoated lens, and measure the working distance.

With kind regards,


Valkir

 

[David Hughes]

This is from memory (meaning suspect) but he also said that on of the Leica copiers (Japanese I think) made all their lenses and bodies at 1mm pitch and then used the hybrid thread.

He also told me that he had worked on (meaning repaired) one of the prototypes from the factory. This was in a discussion about how pioneers worked. I was saying that I suspected a lot of trial and error using "of the shelf" parts from the microscopes. For example the Leitz Mikro-Summar was for microscopes and used as a camera lens.

He also told me that the London/British based Royal Microscopical Society (RMS) originally published the original specifications that standardised microscope parts and that is why Leitz used this standard instead of a more general one for everything. The RMS dates from 1839 but I don't know when the spec. was written.

Back to mix and match; I once calculated that just using standard lenses and bodies I could make 172 variations of LTM camera. Then I decided not to bother!

But I'd love to have the time to do it and the money.

Regards, David

 

[ZorkiKat]

Valkir, it may appear that FED at the time of the 1F's manufacture may have not intended to make these cameras suitable for lens changing. There is no mention of additional lenses in the manuals written (pre or 1950) for these cameras. There is instead an admonition against removing lenses.

Some of the later manuals do say that in case the original lens is replaced, the camera has to be sent to the shop for readjustment.

I have some of these FED-1F types which do appear to have a finer thread pitch than the Leica standard. Threads which are more like the prewar NKVD 39x1mm pitch- the prewar lenses screw on the mounts easily, but the infinity stops are all over the place. Not only that, their focus camming appears to be different too: the travel of the cam from infinity to 1 mtr is much shorter than the Leica's or later FED cameras. When a later FED lens or Leica lens is put in place, the lens won't focus right. I don't have their numbers now, but they are in the 2xx xxx ranges too.

However, I also have other 1F which appear to have standard thread pitches and focus camming. I also have an early unsynched FED-2 which appears to have a finer pitched lens mount so that lenses like the I-26 won't fit on it.

Its really hard to get lenses which can fit and focus on these cameras properly, unless you can pick and test-fit some from a bunch.

 

[ZorkiKat]

This is from memory (meaning suspect) but he also said that on of the Leica copiers (Japanese I think) made all their lenses and bodies at 1mm pitch and then used the hybrid thread.




Regards, David
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David, Canon initially used the 39X1mm pitch on their wartime J type cameras and lenses. But by the time they got the SII and IIb on the production lines, their mount was already 39mm X 1 inch.

Just about all the Japanese postwar clones I've seen (Canon, Minolta, Leotax, Nicca, and Tanack) have standard lens mount threads- Leica lenses fit, and their focus tabs (or tongue shaped cams when applicable) stopped in their proper, expected positions.

 

[sevo]

I have some of these FED-1F types which do appear to have a finer thread pitch than the Leica standard. Threads which are more like the prewar NKVD 39x1mm pitch-

1mm is actually very slightly coarser than the 0.977mm of Leica/Whitworth, and was officially standard until they had to give in to the market forces - during the thirties the Soviets tried to be consequent at metric production. If anybody has a FED with finer thread it would be nice if he could measure it - so far I've only had 0.75mm threaded lenses, but these can just as well have been enlarger lenses, where 0.75mm is and was a fairly common pitch.

 

[ZorkiKat]

1mm is actually very slightly coarser than the 0.977mm of Leica/Whitworth. If anybody has a FED with finer thread it would be nice if he could measure it - so far I've only had 0.75mm threaded lenses, but these can just as well have been enlarger lenses, where 0.75mm is and was a fairly common pitch.

Got the finer/coarser thing mixed up.

I have on hand a Kombinat FED whose lens mount will only allow an Elmar 9cm lens to turn only less than 2 turns before it 'tightens'. Its lens will turn about as much when mounted on a IIIf. Even if these lenses fit on the cameras 'alien' to them focus will be off.

I also tried fitting the Elmar, a Canon Serenar collapsible 50mm/2, and a Canon 35mm on two early "lavatory" seat FED-1 (1935 and 1937). The lenses fit the mounts, but stopped at the wrong places. Strange.

 

[David Hughes]

Interesting, I had the opposite. I got the Elmar and had film in a FED 1f/g at the time and so tried it out and all went OK. The problem arose with the Elmar going into a standard Leica and stopping very soon. (A long time ago and so not a very accurate memory; I can remember what it cost me, though...)

As for my FED 1f's all I have at present are a 239 XXX and a 280 XXX and they seem interchangeable with the Elmars etc. One day we'll all have to get together with all our cameras etc and thrash this out.

The provenance of just two of my FED's or Zorkis is known (both two owner cameras, lenses etc) but that's the snag with them. Very few are pure and a lot seem mixed and matched.

Regards, David

 

[Valkir1987]

Dear Jay and David,

I made a mistake in my first post. I meant to say that the lens mount of the 1F has a different infinity stop. I mistook this for 'thread pitch' !

with kind regards,

Valkir

 

[ZorkiKat]

Dear Jay and David,

I made a mistake in my first post. I meant to say that the lens mount of the 1F has a different infinity stop. I mistook this for 'thread pitch' !

with kind regards,

Valkir

Valkir, the lens, lens mounts, and cameras were matched when they left the factory. I would venture to say that their method involved a selection of lenses with whose varied thread mounts caused their "parked" infinity tabs to stop at positions between 8:00 and 11:00. The persons on the assembly line will then select one which will stop at 9:00 or perhaps even 10:00.

It is really quite difficult to say which lenses will stop at what position since there is really no visible indicator on the lens or the camera mounts. The only way to find one which fits ideally is to test several and pick the one which does best. A lens for instance, which parks at 9:00 on one FED-1g will perhaps park at 11:00 when used on another 1g.

Having the lens park infinity at 11:00 position is still considered acceptable. It's only when the tab stops right in front of any of the windows- 12:00 or 1:00 positions are ridiculous- that the lens is considered unsuitable for the camera. Other than that, focus camming (if the camera is to be used with other lenses) and lens mount thread pitch should be the greater considerations.

 

[Valkir1987]

Thank you, Jay and David

It clarifies a lot. 🙂

With kind regards,


Valkir

 

[David Hughes]

Interesting, I'd assumed they cut the four screw holes in the flange on the body after lining the thread start up on a jig and made the male counter part on the lens oversized. Married the lens part to a standard and then cut back to the stop. That would have been normal but, as we say, there's more than one way to skin a cat. (Sorry ZorkiKat.)

My experience of brand new FSU equipment was that it was old fashioned but "properly" made with all the screw slots lining up and each piece individually tested and so on (and the lubricants stunk). Purely from an engineering point of view they were a pleasure to see. People would get very nostalgic about them and comment on the short cuts that hadn't been taken; no white metal f'instance. The problem was that people wanted design and style rather than substance. And, of course, there are no apprentices around these days to do the donkey work...

Regards, David

 

[ZorkiKat]

David, its quite strange why they ever had the start points of the threads right. Well not until at least when the type G came along. But even then, there are later models like the 2 or 3 whose thread starts and stops were not standard.

Perhaps this is the reason why FSU lenses always came with full round rf cams, instead of having tongue shapeds ones occasionally found in lenses like the Hektor 13,5cm, or the long Canon Serenar lenses. The round cams at least don't need precise stops- it can stop anywhere and still engage with the camera's rf cam.

The Soviets could have had it so easily standardised early on. Even the supposedly more advanced Zorki were not standard in this regard; there was more standardisation in the FED 1g types than the Zorki from the same time, as per my observation with the specimens I have. Could it have been because they assigned the mount flange and lens thread making to so many machines or personnel or even factories that rigid uniformity was impossible?

All the Barnack copies I've seen follow the Leica thread in/stop positions. Even the Chinese made Shanghai 58 conform to this.

 

[David Hughes]

Yup! I'd love a pound note for every time I've said "why didn't they do it this way?" but I don't think we'll ever know.

Regards, David