Sonnar?

[Oldhand]

Just struggling to understand what makes a sonnar design - or a sonnar derived design, for a lens.
Are these two lens designs sonnar derivatives?
I think maybe the first is but am unsure about the second.
Thanks for your input
OH

[Gerald]

This is probably the most comprehensive article on the Sonnar lenses and derivatives:

http://www.marcocavina.com/articoli_fotografici/Bertele_Sonnar/00_pag.htm

The article is in Italian but the Google translator might help.

[Oldhand]

[Gerald]

[IAZA]

This is good source too
http://forum.mflenses.com/list-of-lens-diagrams-triplets-planars-and-hybrid-lenses-t22934.html

[Oldhand]

[uhoh7]

The Real Thing by unoh7, 1937 CZJ Sonnar

jena blue by unoh7, F/8

Superb contrast, great flare resistance.


Shy Friend by unoh7, Wide Open

unique bokeh WO, too wild for some:


L1022938 by unoh7, on Flickr

Descended from the Ernostar, first candid low light system, the above lens was the first to bear the "Sonnar" name, I think. It was definitely the lens which made the reputation.

another very famous sonnar:

Nikkor S 85/2 by unoh7, Nikkor 85/2 Sonnar 220,000 made.


Menus by unoh7, on Flickr

and the fastest Sonnar ever made:

Sonne by unoh7, Sonnetar 50/1.1 circa 2015


Coffee Baron by unoh7, Sonnetar on M9


Cold Comfort by unoh7, Sonnetar on A7.mod

What do they have in common besides a similar formula? Hellacious sharp centers. Great contrast, old or new. A bokeh which becomes charming and identifiable once you drop from the fastest speeds.

But if you insist on the extremes:

Vic by unoh7, Nikkor 50/1.4 Sonnar.

The bokeh will become a major part of the composition.

[kds315*]

I always liked them, Dr Bertele did a fantatsic job in creating them!
Great examples!!

[LucisPictor]

Amazing images, unoh7!!

What a beautiful young lady!
And Anthony Hopkins in the last frame is also well captured.

[vanylapep]

How do lens design work?

Somebody comes up with a "Sonnar" design, then whoever design lens like the "Sonnar" blueprint has to pay license/royalty/copyright fees?

Same for Planar design? What are all the possible lens designs?

[kds315*]

[scsambrook]

Patents are interesting things which have ramifications which sometimes get overlooked.

Patents have a limited life, typically for 15 years in the days when these design appeared. Hence the plethora of "Tessar" and "Planar" patterns which came along once the patents had expired. Furthermore, depending on what exactly is protected by the patent, it may have been possible to create a design which although following the general principles of a "Tessar" or "Planar" was sufficiently different to avoid infringement. Patent protection was far from absolute or straightforward in some cases.

Sometimes the real degree of protection was eroded by other countries' own patent laws. In Britiain, for instance, a 1907 law required that if an "invention" (such as the Tessar lens design) was not being "worked" (i.e. manufactured) in Britain, then a domestic producer who wished to make it had to be granted a licence by the patent owner, irrespective of where he was located. To add to the difficulties of the holder of the patent, he was not permitted to demand an exhorbitant price for either the licence or royalties on units manufactured. The only means to maintain an absolute monopoly of the patented design was to set up for manufacture in the UK. Both Zeiss and Goerz opened what were claimed to be British manufacturing plants after 1907, although it's unclear as to whether they actually made anything, as opposed to assembling German-made components. Both had earlier licenced English firms to make their designs and by creating "factories" it's probable that they planned to refuse renewals when the originals expired..

[woodrim]

Very nice collection of lenses, Uhoh.

[stevemark]

[uhoh7]

TY for kind words

I have two RF 105/2.5 lenses (one is for contax)


DSC05920 by unoh7, on Flickr


a7r_nikkor_105mm_RF by unoh7, on Flickr


DSC01984 by unoh7, on Flickr

As most of you know, this lens was totally re-designed to make the later famous 105/2.5

I also have a 135/4 Zeiss pre-war, which I think is a sonnar It's pretty beat up, but I should get some samples.

[kds315*]

[Gerald]

Today Sonnar is just a trade name owned by Zeiss with maybe a single exception I will comment later. That is, the name Sonnar as used by Zeiss and Sony has no longer any technical meaning. Even in the past, there were so many variants of Sonnar (well described in the article by Marco Cavina) that the concept of Sonnar became a little confused.

The hallmark of the Sonnar lenses was a thick and heavy cemented triplet. In the CZJ Sonnar 180mm F2.8, which was a very common lens for use with Pentacon Six cameras, only the front group with the cemented triplet weighed 560 grams. In comparison, a complete Olympus Zuiko 180mm F2.8 weighed only 700 grams. You can imagine how many tons of optical glasses were consumed in East Germany just to produce so many Sonnar 180mm F2.8 lenses!

The truth is that the Sonnar designs for fast normal lenses (focal length around 50mm and apertures larger than F2) were surpassed by the Double Gauss design, which became dominant after WWII. The reason for the dominance of the Double Gauss design is that it is a symmetrical or quasi symmetrical structure, what enables excellent correction of coma and lateral chromatic aberration. In contrast, in a Sonnar design, those aberrations are not as well corrected, with significant softness on the edges.

Zeiss still sells a lens called C Sonnar T* 1.5/50 ZM for Leica M cameras. This lens does not have the characteristic front triplet of the Sonnar design, but nonetheless the C Sonnar suffers from all the typical aberrations (Zeiss call them "effects) of the classic Sonnar 50mm F1.5 from before the war. The C Sonnar is a controversial lens with strong focus-shift and off-axis aberrations, and these defects are so significant that Zeiss walks on eggshells when describing the lens:

"This lens design exhibits some additional effects, which should be understood to achieve the maximum benefit from the C Sonnar T* 1.5/50 ZM: Because of the above mentioned classical characteristic of the lens the best focus position in the object space can not be kept exactly constant for all f-stop settings. The passionate photographer might notice a slightly closer best focus in his pictures than expected. When stopping down the lens to f/2.8 or smaller this effect is minimized, so the focus position will be as expected. In order to balance the performance at full speed and other f-stop settings the lens is adjusted with above described characteristic. The special features of the C Sonnar T* 1.5/50 ZM are best used in emotional, artistic, narrative images, portraits or atmospheric landscapes. For documentation or technical subjects Carl Zeiss recommends to stop down the lens at least to f/5.6 or to use the Planar T* 2/50 ZM lens."

Note: "Emotional, artistic images" is just a polite way to say the lens is full of aberrations…

[scsambrook]

[Gerald]

[scsambrook]

Gerald - many thanks for pointing out that there are design differences between the "old" and "new" Sonnars, although I think that it had actually been mentioned in an earlier post. What I am hoping to learn is whether the new design has some quirks that are absent in the earlier one - or vice versa.

By "internet regurgitation syndrome" I mean the all too common tendency for some people to repeat the unsubstantiated assertions of others as though they are demonstrable or reliably documented facts. I'm sure MFLenses regulars would never fall into that category.

[uhoh7]

Stephen, the modern ZM50/1.5 I don't think would be confused with the original. The modern one has a different palette, and is better on the edges at all apertures. Search flickr for ZM 50/1.5 and you get a ton of samples. It's a superb lens, and certainly the best sonnar 50 from the look of it on numerous bodies. Great bokeh and very modern Zeiss colors, yet a hint of the classical render. I was very impressed.

It has a flawed reputation because of focus shift you get with rangefinders. But in reality this can be easily learned.

Looks like my old 1937 135 is another "Sonnar"


Zeus 135/4 by unoh7, on Flickr


Zeiss 135/4 by unoh7, on Flickr


DSC08624 by unoh7, on Flickr


DSC08626 by unoh7, on Flickr


DSC08627 by unoh7, on Flickr

Great in the center, but the edges are weak compared to a good modern 135. These on the A7.mod

[scsambrook]

uhoh7 - thanks for the observations and nice photos! I've read about the focus shift peculiarity on the modern Zeiss 50/1.5 and wondered if the original had similar behaviour.

[uhoh7]

[scsambrook]

Thanks again for the observations, uhoh7. I smiled at your comment about people having kittens if the calibration is off - I have one fast Leica RF mount medium tele lens of Sonnar pattern which "back focuses" by about 20mm at close range as you stop down from wide open to F5.6; although noticeable when taking shots of rulers and tape measures, it never seems to matter in real-world photography. And I have another fast 85 (not a Sonnar design) which despite having a reputation for shifting focus is apparently immune to it.

[pavko]

Does anyone know if lens mounted to Rollei A26 (Sonnar 40/3.5) is realy of sonnar design? Or is it just marketing and in fact it is tessar/ernostar derivative?