Fed 2/50 lens: a coated one???
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Topic
Topic author: Jacques M.
Posted on: 20080807073926
Hello,
Yesterday, I received one of the last 2/50 produced, as far as I know: the serial # 32649 (to put on my 180xxx S eBerdsk).
I was surprised by the first lens which shows blue/lilac reflects which don't exist on my six other 2/50 Fed lenses, as if this one was single coated.
My question of course, is: is it possible? When?
If yes, it would be important for the understanding of Fed S 1e-s periods of making, as there is a strong correlation between S bodies and 2/50 lenses...
Amitiés. Jacques.
Replies
Reply author: stephanvdz
Replied on: 20080807112151
I didn't coated it... I swear... perhaps it came because it was hidden in my collection of T lenses ;-)
seriously I never remarked that... and it came on my FED S number 107723 but someone has mixed the lenses
Note that for me that lens was unusable, because it's out of focus in the all range...
Good luck at finding wat is wrong...
Wat if it was not a fed lens ?
Stephan
Reply author: Jacques M.
Replied on: 20080807151314
Hi all (and Stephan!)
No doubt this is a Fed lens!
I checked its optical possibilities: it is completely out on the complete range, as Stephan says. It's easy to compare roughly two identical lenses. This one was certainly dismantled to be repaired, and the different optic groups of lenses were badly re-mounted.
All that doesn't explain the apparent coated lens... To my mind, it's the point which could be interesting. And the specialized books don't give any explanation.
Amitiés. Jacques.
Reply author: nightphoto
Replied on: 20080808102931
Hi Jacques,
Maybe when it was dismantled and reassembled, the front element or element group was replaced with a coated element or group. Maybe that is why it was dismantled ... because the front element was damaged.
I have a FED-S Berdsk # 179348 and it has the original lens # 29484. The lens is not coated.
Bill
Regards, Bill
Reply author: Jacques M.
Replied on: 20080808110848
Hello,
I have just partially dismantled that lens and compared it with another 2/50 lens I own: the n° 27957.
The two rear units are identical: same aspect, same convergence.
It's not the case of the front part. The 32649 is globally much more convergent. The very front lens seems more curved and thicker (I took it away), so that the ring cannot be screwed completely in the barrel to fix this lens. It's this first unit which is coated.
Of course, impossible to take pictures with this lens mounted on a Fed S or any LTM. Perhaps the work of a handyman to sell its lens? Or a trial of the factory for an hypothetic 39mm small format in 1941 or after WW2...?
Amitiés [:)]. Jacques.
Reply author: Jacques M.
Replied on: 20080809072634
Hi!
Sorry for this serial film!
As the ring cannot be completely screwed to secure the very first lens, there are two millimeters which protrude. And the screwing aluminium cover is exactly 2 millimeters larger than the ordinary one to enclose all that. The work is perfect. I try to join a picture.
So that is hardly noticeable that the lens 32649 is very slightly larger than the 27957.
All that makes me think this lens was made by the factory. But when? And above all , why?
If you have ideas...
Amitiés. Jacques.
Bill, you say your "couple" 179348/29484 is original. Interesting! Do you have a passport or something?
Reply author: Jacques M.
Replied on: 20080809073314
Reply author: Jacques M.
Replied on: 20080809075200
Reply author: nightphoto
Replied on: 20080809143249
Hi Jacques,
No, unfortunately I don't have a passport. I think it is original because I bought it here in the United States from a Russian man who was not a dealer, and he told me that it had been his father's only camera and bought near WWII. So this is why I think it.
Yes, my lens has the thinner ring on the front like your uncoated example. It does seem that your coated lens has a thicker ring and must have been made by the factory.
I don't know why this was done or what camera it could fit on, unless the lens was made to fit onto a reflex housing device that would be mounted to the FED rangefinder (sort of like the FS-2 fotosniper from WWII).
Also, I have noticed that the only other serial number as high as your lens, on our WIKI list of FED-S cameras, is the last one on the list, which is a little higher, and is owned by Claudio Asquini and he calls it a "Sonnar"! So maybe this is clue?
Regards, Bill
Reply author: Jacques M.
Replied on: 20080811100305
Thanks, Bill.
I'll try to have this lens optically analysed after the holidays.
Why not this lens for a fotosniper effectively: the dates and the history of Fed would fit.
For Claudio Asquini's lens:
http://www.geocities.com/RodeoDrive/8595/chilavist.htmlIt seems a real Sonnar with the mounting of a Fed lens...
This camera is dated from 1948. Surprising!
Amitiés. Jacques.
Reply author: Luiz Paracampo
Replied on: 20080812065222
<font size="1">It seems a real Sonnar with the mounting of a Fed lens...
This camera is dated from 1948. Surprising!
Amitiés. Jacques.</font id="size1">
------------------------------------------------------------
A <u>Sonnar</u> (Zeiss) lens formula will never fit in such barrel !
This is a Real <u>SUMMAR</u> (Leitz) formula lens.
Regards
LP
Reply author: Jacques M.
Replied on: 20080812090238
Hello Luiz,
You mean that Asquini's lens would be a Summar reingraved Sonnar with a Fed mount?
Jacques.
Reply author: stephanvdz
Replied on: 20080812173513
no it's a collapsible sonnar head on a fed 50/2 barrel, "easy" modification
Stephan
Reply author: Jacques M.
Replied on: 20080813031643
It's what I think, too.
And the number gives 1941 as the date of making: not bad for an 1e...
Jacques.
Reply author: Luiz Paracampo
Replied on: 20080814182153
Jacques
Repeating Stephan words........."a collapsible sonnar head on a FED 50/2 barrel"..........
LP
Reply author: Jacques M.
Replied on: 20080814222943
Hi Luiz,
I don't see any difference with what I said...
Probably my english!
Jacques.
Reply author: stephanvdz
Replied on: 20080815111455
Jacques
Could you see if it creates an image, and how far from the flange... ?
Stephan
Reply author: Jacques M.
Replied on: 20080817104357
Hi Stephan,
Yes, there is an image which occurs at about 12/13 mm from the interior part of the flange.
I cannot be more precise for the moment.
Amitiés. Jacques.
Reply author: stephanvdz
Replied on: 20080818102006
that's bizarre...
bizarre, j'ai dit bizarre... comme c'est étrange
Stephan
Reply author: Jacques M.
Replied on: 20080818115831
[:D]
With exactly the same method, I obtain an ordinary c.29mm with another 2/50 mm Fed lens.
Perhaps a specialist in optic could tell us more [?]
Amitiés. Jacques.
Reply author: stephanvdz
Replied on: 20080819163926
may be you should try to put the front lens the other way... reverse it...
Stephan
Reply author: stephanvdz
Replied on: 20080922170508
no news... have you lost hope or is this thing really not working ?
Stephan
Reply author: Jacques M.
Replied on: 20080923105642
Hi Stephan!
I cannot reverse the front part of the lens as it is too curved. Really, I don't know on which body it could work...
Amitiés. Jacques.
Reply author: Brian
Replied on: 20130102190000
Looking at the Fed lenses: my first guess is that someone substited a front element, possible from a J-8, for one that was damaged. This will be the wrong focal length and "looks good" but will not focus correctly. I was sent a 1951 J-3 all the way from Russia to look at, likewise it would not form an image. The rear glass was "wrong", someone stuck something in from a Planar just to make the lens complete. The front element and front triplet was perfect, and all went happily into a new optical fixture with a slightly later rear triplet.
On this one: if you can measure the focal length of the front element from the working lens, and the diameter of the lens you might be able to find a good substitute. I was able to replace the rear element missing from a Nikkor 10.5cm F2.5 with one from surplusshack.com. "it worked"
Reply author: Jacques M.
Replied on: 20130103043552
I will try to examine it more closely.
The change of the front module, why not?
At this point, how can we explain the cover which is 2mm larger?
Jacques.
Reply author: Brian
Replied on: 20130103143041
It's hard to say what has been done to lenses over 60 or more years. I bought a pre-war 5cm f1.5 Sonnar that was missing the middle triplet and had a front element of 100mm focal length to make the lens a 50mm overall focal length. It formed an image: but had wild distortions.
The early Nikkor 5cm F1.4 lenses have optics and fixtures that are smaller diameter than those made a year or so into production.
I've bored-out the fixture of a Rigid Summicron to replace the front element with one slightly later.
Hard to tell what's been done.
Reply author: stephanvdz
Replied on: 20130103170801
Jacques, did you try it on a zenit 39 ?
It would be very surprising, but why not ...
Stephan
Reply author: Jacques M.
Replied on: 20130104053352
I try to find a M39 Zenit. If not, I will buy one: it's worth trying. It would be crazy: it would mean that Fed was associated to the SLR KMZ work...
Thanks for the idea.
Reply author: stephanvdz
Replied on: 20130104123156
or may be that the 39reflex standard was not a KMZ invention... it's the same frange distance than the M42... and may be the M40... so...
Stephan
Reply author: Brian
Replied on: 20130105075347
Before buying a camera- put a white oiece of paper, or cardboard, on a table under a light. Hold the two lenses to form an image of the light on the paper. If you have to hold the mystery lens "about" 20mm farther from the paper to form the image, and the formed images- might work on an SLR.
If you have a mirrorless camera, might work on it.
Reply author: Jacques M.
Replied on: 20130105115008
The time to find out the lens, and to make other comparisons...
I confirm: there is about 20mm difference between the images with this lens and an ordinary 2/50 Fed lens, all parameters being the same.
But it is with the ordinary lens that the formed image is farther...
Reply author: Brian
Replied on: 20130105133130
It sounds like the lens has mismatched optics in it. The back-focus on the odd lens is much too short to be useful on a camera.
Reply author: Jacques M.
Replied on: 20210529045516
