Compare the Old and New Sonnar 1,5/50

When you compare the structure of the old and new Zeiss Sonnar 1,5/50, you can see the basic structure is the same, however, the old Sonnar has one more glass:

Some Comments about Tessar, Sonnar and Elmar (Part One)

This Artical is originated from Wah of Contax Club:

小弟唔係光學專家...........不過既然係 Leica 野就用番 Leica 界權威 Erwin Puts 既言論討論一下.......

1. Leica M-lenses

http://www.leica-camera.com/imperia/md/content/pdf/msystem/49.pdf

在 Page 42, "The first lens used for the Ur-Leica had a focal length of 42mm. Commercial models (from 1925) were fitted with the Anastigmat/Elmax f/3.5/50mm. This design had 5-elements, presumably to avoid patent conflicts with the Zeiss company........."

小弟對於 Kino-Tessar 50mm 既質素當然未能理解.........不過世界上就真係一樣唔知係造福人群定係遺禍人間既發明.........就係叫 patent

想當年 Elmar 50/2.8, Elmar 50/3.5 既設計都係以 Tessar 為藍本.........不過光圈位置就與 Tessar 不同, Leica 的設在第一組與第二組之間, Tessar 的就在第三組與第四組複合鏡片之間. 對於此設計, Erwin Puts 有此評論:

(同樣 Page 42) "The Elmar f/2,8/50mm was introduced in 1957, almost 33 years after the Elmar f/3,5/50mm. In its day, the Elmar f/2,8 was famous for its very good image quality in the center. It was also slightly ahead of perennial competitor Zeiss
with the Tessar. The different position of the aperture (between the first and second element) was the main advantage of the Elmar. On test the Elmar performs acceptably, at full aperture with a low overall contrast and clearly rendered fine details with smooth (more accurately: soft) edges..........."

當然 Elmar 係不少 Leica fans 既摯愛........由其以 Red-scale version 最受追捧! 是由於使用稀土玻璃之緣故..............小弟則相信, 以 Tessar 此相對簡單之設計下, 對於鏡片組裝與鏡片質素上既要求其實更高, 任何廠家 (Voigtlander, Nikon, Canon) 只要有誠意制作個人覺得質素不會相差太遠.

而當年的 Voigtlander (未被 Zeiss 收購前)既 Skopar 都係用 Tessar 既一套...

http://www.taunusreiter.de/Cameras/Bessa_RF_histo_dt.html

不過.........既然 Leica 係製造 Tessar 一類鏡上有如此獨門秘方..........小弟就不知如何解釋其後推出既 Elmar-M 就用回 Tessar 既設計..........或者係 original Elmar 既設計生產成本高昂?

另外一個解釋係..............Tessar 係 2002 年慶祝 100 歲生日

2. 至於1933 年推出既 Summar 50/2 (參考 LEICA LENS 不朽之名玉 203, Page 104), 其根本 design 就是 Double-Gauss, 以當年 35mm 相機市場計, 由於 coating 問題, 以 Double-Gauss 所設計既大光圈鏡由於玻璃介面比較多既關係 (如 Summar, Xenon, Summitar 一類) 一直被 contrast 較高, Flare 及 玻璃介面比較少的 Sonnar 50/2 及 Sonnar 50/1.5 所比下去. 不過以市場先決原則, 就算性能上是以 Elmar design 佔優, 但又怎可錯過大光圈標準鏡的市場 (以當天 ISO 50 為高速菲林計............)

Carl Zeiss lenses for the Contarex

Carl Zeiss lenses for the Contarex
There's hardly more myth and legend in the photographic world than that which has been built-up around Carl Zeiss lenses. Let's try and have an open-minded look. Admittedly, I was intrigued by the famous names when I found myself quite unexpectedly in the possession of a Planar, a Biogon, a Distagon, and an assortment of Sonnars. One thing was immediately apparent: the extraordinary finish quality. Heavy, solid metal barrels with a slightly matted chrome finish and a smoothness and precision of the focussing mechanism which must be felt to believe it, even after so many years. Just look at the picture. This arrangement wouldn't seem out of place in a jeweller's window. So, let's have a look at a series of pictures I've taken with the different lenses and find out more about them. I'll show a scaled-down version of the full frame just to demonstrate the angle of view of each lens. Clicking on any of these pics will load a small section of the corresponding negative scanned at the full 2700 dpi resolution of my Nikon LS-30. Biogon 4.5/21 mm (lower left, with external viewfinder next to standard lens) This lens was first made for the Zeiss-Ikon Contax rangefinder cameras and it caused a big sensation when it was introduced at the 1954 Photokina. Before the Biogon, conventional wisdom had it that an extreme wide angle lens had a maximum opening of f8 and considerable distortion. Even by today's standards, the linearity of this lens is quite amazing. Due to its symmetrical design with a rear element which almost touches the film, the mirror has to be moved up before mounting it and there is an external viewfinder which is fastened in the accessory shoe. Unlike most Contarex lenses, the Biogon has its own iris setting ring. It can only be used with the original Bullseye and the meterless Special. It would collide with the metering cell, in later Contarex cameras. This has become one of my favourite lenses. It covers exactly my eyes' field of view including peripheral vision. I love the immensely wide view and the absence of the distortion which makes most pictures taken with other extreme wide angle and especially fisheye lenses look so boring, after some time. Distagon 4/35 mm (right, next to standard lens) This is a retrofocus design which has been developed especially for the Contarex. Though quite slow by modern standards, its optical performance is very good. This lens can be focussed down to 19 cm from the film plane or a mere 10 cm from the front ring. At this short distance, the aperture is automatically opened up slightly to compensate for the light loss. The low speed isn't much of a problem, though, because this lens can be used wide open without any visible loss of sharpness. Planar 2/50 mm (standard lens, on camera) Following over half a century of Planars on medium format cameras, this is the first 50 mm Planar lens made for a 35 mm camera. The minimum focussing distance is 20 cm from the front ring, again with automatic aperture compensation. Planars are generally known for their low distortion and high quality and this one is no exception. Sonnar 2/85 mm (far right, behind lens hood) This lens had originally been developed for the Contax rangefinder cameras. Its design of seven elements in only three groups makes it very resistant to flare, even as a single-coated lens. Due to its high speed and shallow DOF at full aperture, this is a wonderful portrait lens. Bokeh fanatics will love this one. Sonnar 4/135 mm (upper right) Like the 85 mm Sonnar, this one has also been borrowed from the Contax series. A very solid performer which makes good for its rather meagre opening by being corrected to be used at full aperture. . Sonnar 4/250 mm (shown below) With a length of 20 cm and a weight of 1400 g, this is a real monster of a lens. It has its own tripod bushing which can be rotated by 90 degrees for vertical shots. The finish and construction are wonderful and the optical performance is excellent, but the ergonomics of this lens are simply terrible. The focussing ring is the lowermost silver ring, in the illustration below. Now, hand-hold this lens and the camera and try focussing it... Certainly, the Zeiss engineers hadn't intended this lens to be used without a tripod. This is also the only of the original Contarex lenses that needs to be stopped down manually. Later versions of this lens had a newly developed focussing arrangement with a knob on the side of the barrel. This is the original set of lenses made for the Contarex. In later years, a number of new products were added. Notable additions were a 2.8/25 mm Distagon, a 1.4/55 mm Planar, the famous 500 and 1000 mm Mirotar catadioptric lenses as well as 18, 16, and 15 mm Distagon designs. The famous 2.8/180 mm Olympia Sonnar was also made available. More exotic offerings included a Schneider PC Angulon 35 mm shift lens, the peculiar Zeiss monocular, and two Vario Sonnar zooms where the usual Zeiss perfectionism had led to such bulk and weight that they were practically useless. So, what's the verdict? The Zeiss glassware beat s everything I've ever used hands down with the exception of the already mentioned ergonomic shortcomings and a few flare problems due to the fact that none of these lenses is multi-coated. After all, they're 40 years old. Other than that, they're great. Beautiful by their extreme sharpness as well as what we have come to know as bokeh in the out-of-focus portions of the pictures. I'd certainly hate to be without them again. Now, if only the 25 mm Distagon at my local dealer wasn't quite as expensive.....

This story is originated from http://www.fotoralf.de/contalens.htm

Zeiss-Ikon Contarex I

This story is originated from http://www.fotoralf.de/contarex.htm

This is now my 'main' camera. I inherited it, in the early summer of 2000. The aperture control wasn't working and the shutter was out of order at the fastest speeds. Still, there was a full complement of Carl Zeiss lenses, from 21 mm to 250 mm, all in pristine condition. I sat down with the camera body and after two hours and some micro-surgery on a spring which had disconnected itself at one end, I had the aperture lever inside the bayonet stop down the lenses again. Pheeewww.... The shutter was later taken care of by Gima GmbH of Munich, a repair service specialized in Zeiss Ikon equipment, together with a complete CLA of the camera body. Some History The Contarex I was first shown at the 1958 Photokina and became available in early 1960 for a hefty 1,060 deutschemarks including the 2.0/50 mm Carl Zeiss Planar standard lens. In those days, the price of a two-pound loaf of bread was 1 DM, a tram ticket was 0.50 DM, and my parents paid a rent of 80 DM per month! Makes a Nikon F5 look like a real bargain. Some 32,000 of the original 'Bullseye' or 'Cyclops' were made until 1966 and, together with the later models, contributed a lot to a growing financial deficit which eventually led to the end of all Zeiss Ikon camera production, in 1971. Technical aspects There are a few characteristics which differ so much from today's SLRs that they deserve an explanation. The most prominent feature certainly is the lightmeter which has earned this camera its nickname. Ironically, TTL metering should be pioneered by the estranged Eastern relatives at Dresden. One of the many novelties with this design was the cross-coupling between the speed and aperture settings and the exposure meter. It does, however, work a little different from the more modern versions and this also explains why Contarex lenses have no aperture control ring. The aperture is set by a small knurled wheel at the front of the camera body which is geared to a second iris in front of the exposure meter's selenium cell. Thus, the amount of light reaching the meter is directly linked to the pre-selected lens aperture. A potentiometer under the speed dial provides the speed information for the light meter and completes the circuit. The most practical thing by far about a Contarex are the backs. Like with some medium format cameras, they can be swapped in mid-roll without having to rewind the film or losing a single frame. A system of interlocks prevents accidents like taking off a magazine without closing it first. They can be changed in a matter of seconds. During a recent holiday on Mallorca, in late November, the days were short but very bright, there were a number of beautiful shots to be taken around dusk and dawn, I did a lot of nighttime shooting at the Soller tram depot, and I like B/W, as well. Four mags loaded with Supra 100, 400, and 800, plus one with XP-2 made sure that everything could be done with exactly the right film. The very bright viewfinder has been realized by means of a fresnel lens instead of the more common matte screen. The disadvantage of this is that there is no DOF preview and no way of focussing just anywhere on the screen without using the split field and micro-prism focussing aids. To complete the description of the camera body, here's a quick run-down of the key features and specifications: shutter speeds from 1 to 1/1000 sec plus B focal plane shutter instant -return mirror focussing at full aperture exchangeable backs wide choice of accessories for scientific and macro photography 'data strips' for including written data on the negative exchangeable focussing screens with the later 'D' series dimensions with Planar lens (whd): 155 x 100 x 105 mm weight with Planar lens: 1,300 g (3 lbs !!!) Am I happy with it? I'm happy with the picture quality it delivers. The workmanship is simply adorable. It's a beauty and the greatest working conversation piece I've ever had. On the downside, the ergonomics are a disaster by modern standards, and everything is so heavy that, in this household, my Tamrac bag with the body and the lenses plus a few backs and accessories goes by the name of 'The Millstone'. But those Zeiss lenses really are worth it all and I do love the exchangeable backs, an extremely rare feature for a 35 mm camera.

Click here for a description of the Zeiss lenses for the Contarex

C-Sonnar 1,5/50 ZM Sample Pictures

http://www.cosina.co.jp/seihin/co/c-s-50/akagi/index.html

Zeiss talks about C-Sonnar 1,5/50 ZM

This is what Zeiss talks about the C-Sonnar 1,5/50 ZM - Focus shift during aperture change, especailly in F1.5 and F2

C-Sonnar T* 1,5/50 ZM

Information about special features for dealers and users

The C-SONNAR T* 1.5/50 ZM is a very special lens; based on a classical lens design concept from the 1930´s. The additional letter “C” in the name of the lens expresses this designation.

This lens design helps to achieve pictures with a special artistic touch. This lens ‘draws’ your subject in a fine, flattering manner and is therefore ideally suited for portraiture. It renders a sharpness that is slightly rounded, being less aggressive than in contemporary lens designs, but at the same time not soft in its rendition.

Many famous portraits of glamorous and prominent people during the 1930´s used this technique to great effect. These images are characterized by portraying the person in a shining, nearly celestial way. This effect is very well balanced and not exaggerated; therefore many viewers see it in a subconscious way. The trained observer, however, understands the underlining technique and enjoys the results.

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.

Zeiss M-Mount Lenses Review in Luminous Landscape

http://www.luminous-landscape.com/reviews/lenses/zeiss-m-mount.shtml