>I noticed that the rear optic group has its lenses mounted on screwed modules that does
>not have any shims. It is simply glued in place at a certain position, not fully screwed.
Hard to believe that there were not any shims on the rear group! It makes sense that they could be set for either the Contax standard or the Leica/Nikon standard. I reduced the rear (secondary) shim on a Helios-103 to adapt to the Nikon focal length. Moved the rear group in closer to reduce focal length. Also did the same thing with a post-war 50mm F1.5 Sonnar that was given to me. It had issues, the groups were out of whack when I got it. No secondary shim, had to file a bit to move the groups in.
>not have any shims. It is simply glued in place at a certain position, not fully screwed.
Hard to believe that there were not any shims on the rear group! It makes sense that they could be set for either the Contax standard or the Leica/Nikon standard. I reduced the rear (secondary) shim on a Helios-103 to adapt to the Nikon focal length. Moved the rear group in closer to reduce focal length. Also did the same thing with a post-war 50mm F1.5 Sonnar that was given to me. It had issues, the groups were out of whack when I got it. No secondary shim, had to file a bit to move the groups in.
Wow. You got so carried away you did not answer the question that you quoted.
It turns out that the answer is, by the way, N. Nikon RF mount 50/1.1's have a capital N on the lens mount. The Contax RF mount 50/1.1's are plain, without a N or a C.
Stephen
Roger Hicks
Veteran
If it is a 5-group, 9-glass lens then it's hard to defend it as a Sonnar derivative rather than as a Cooke Triplet derivative. A Sonnar is, after all, a Cooke Triplet with the singlets replaced by cemented doublets or triplets; as soon as there are more than 3 groups, it's highly disputable whether it is truly a Sonnar or not.
My suspicion is that because Cooke Triplet doesn't sound very expensive, and Sonnar does, people use the the 'Sonnar' label instead. Also, of course, you need to know a little about lens design to understand the Cooke Triplet family tree, whereas 'Sonnar' is known even to people who have only the slightest acquaintance with lens design through the internet.
The fastest triplet derivatives of which I am aware are the Rodenstock XR- and TV-Heligons at f/0.75, with image circles of 15-16mm: 7-glass, 4-group and 9-glass, 6-group. You'd be pushing it to call them Sonnar-type.
Tashi delek,
R.
My suspicion is that because Cooke Triplet doesn't sound very expensive, and Sonnar does, people use the the 'Sonnar' label instead. Also, of course, you need to know a little about lens design to understand the Cooke Triplet family tree, whereas 'Sonnar' is known even to people who have only the slightest acquaintance with lens design through the internet.
The fastest triplet derivatives of which I am aware are the Rodenstock XR- and TV-Heligons at f/0.75, with image circles of 15-16mm: 7-glass, 4-group and 9-glass, 6-group. You'd be pushing it to call them Sonnar-type.
Tashi delek,
R.
With lenses in this speed range, the designers usually started with a known formula, scaled it up for the faster speed, and split one or more element into two elements of lesser power or split a cemented group into a group+ element or a group with more cemented elements.
The original Planar was a 1-2-2-1 formula with symmetric configuration. The Xenon improved it for higher speeds by making the front/rear sections asymmetric. The Summarit was a classic 1-2-2-1 split into a 1-2-2-1-1, but everyone calls it a Planar. Nikkor 5.8cm F1.4 is a 1-1-2-2-1 configuration. And the Bokeh looks like a Summarit. The Simlar split it into a 1-3-2-1 and some call it a "half Sonnar". I believe it was derived from a Planar, as starting with the 1-2-2-1 and splitting the forward group makes the most sense. Starting with a Sonnar front end and trying to generate a rear module to correct it- HARD!
Without seeing the computations for the lens and how the designer acheived the final design, its hard to say what he started with. The results are a unique optical formula. Did he start with a Sonnar ot a Triplet? Easier to start with an existing Sonnar design and start splitting elements and groups. The Sonnar is derived from a triplet. Is the lens a Sonnar or a Triiplet derivitive? Inclusive .OR. is .TRUE.
And getting a Zunow 5cm F1.1 without a marking- probably just move the rear module in closer. I winder if someone did that with the lens shown, took out the rear shim, and glued it in place to use with a Nikon. I mark my Zeiss and FSU lenses "Nikon" when I modify them. And I File the secondary shim down for the Helios.
The original Planar was a 1-2-2-1 formula with symmetric configuration. The Xenon improved it for higher speeds by making the front/rear sections asymmetric. The Summarit was a classic 1-2-2-1 split into a 1-2-2-1-1, but everyone calls it a Planar. Nikkor 5.8cm F1.4 is a 1-1-2-2-1 configuration. And the Bokeh looks like a Summarit. The Simlar split it into a 1-3-2-1 and some call it a "half Sonnar". I believe it was derived from a Planar, as starting with the 1-2-2-1 and splitting the forward group makes the most sense. Starting with a Sonnar front end and trying to generate a rear module to correct it- HARD!
Without seeing the computations for the lens and how the designer acheived the final design, its hard to say what he started with. The results are a unique optical formula. Did he start with a Sonnar ot a Triplet? Easier to start with an existing Sonnar design and start splitting elements and groups. The Sonnar is derived from a triplet. Is the lens a Sonnar or a Triiplet derivitive? Inclusive .OR. is .TRUE.
And getting a Zunow 5cm F1.1 without a marking- probably just move the rear module in closer. I winder if someone did that with the lens shown, took out the rear shim, and glued it in place to use with a Nikon. I mark my Zeiss and FSU lenses "Nikon" when I modify them. And I File the secondary shim down for the Helios.
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Vickko
Veteran
Congratulations
Congratulations
Congratulations on your find.
I've been casually looking for one of these for years. It's the last "fast glass" to find, to fill a gap in my collection.
...Vick
Congratulations
Congratulations on your find.
I've been casually looking for one of these for years. It's the last "fast glass" to find, to fill a gap in my collection.
...Vick
Mael
Established
The rear group is crimped in place in a brass mount, that has a female helicoid, but this whole rear group is screwed on the lens body without any shims. There is still turns to go. And it is physically impossible to put shims here, because there is no flat surfaces for the shim to stand, nor inside, nor outside. It is the first time in hundreds on lens dismounting I ever see this. I noticed that some resin has been put on the thread. It was very cleanly done, and it was clearly aplied to have the rear group in place at a precise position. Has there was no haze in this rear group, I did not touch anything.
The lens did not have any markings on its body. I purchased this lens with a Kiev IV. The Kiev was approx. registered to the Contax standard, but did not focus properly with this lens. On the other hand, the focus was absolutely perfect on the S3 2000.
Perhaps this lens has been modifyed to be used with Nikons, I don't know ! The lens is now sold, and is making the pleasure of a sympathetic RFF member.
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NIKON KIU
Did you say Nippon Kogaku
Before this thread joins destiny, I'll post a picture from a recent Westlicht Auction:
Kiu
Kiu