SidW
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Post by SidW on May 25, 2007 9:27:52 GMT -5
I was surprised at the image quality of the 135mm/4 Zeiss Triotar (humble truplet) and wondered how much better the 135mm/4 Sonnar might be. I've now had a chance to make a first comparison. This Triotar is the manual preset aperture version of the 1950s (subsequently discontinued). The Sonnar is a later auto "zebra" version from 1970s. The latter has better colour correction, very evident in the pictures because the Triotar transperencies have a heavy blue cast and needed more colour adjustment. The Triotar turned out to have a slightly narrower angle of view. Exakta Kine II (1949), Kodachrome 200. One series with each lens at diferent apertures, in one session. Subject: a Hepatica nobilis flower in the local woods, focused on the stamens, first image in hazy sun, then the sun gradually cleared as the session progressed. Handheld (there is a philosophy that you should compare lenses using your usual working method). 10cm extension ring, i.e. modest macro at about 50cm distance. Triotar 1/250 f:4, uncropped Sonnar 1/250 f:4 (clearer sun), uncropped I find it hard to see any difference between them. If anything, it just proves I had difficulty focusing. I'd forgotten how much easier it is to do handheld close-ups with more recent cameras (TTL metering, eye always on the subject etc, faster action). The Exakta really is a tripod camera, especially for macro work and with manual lenses. The next picture shows small crops at 100% zoom for comparison: Photobucket has scaled this down about 5-10%. 197x197px crops from 100% zoom (i.e. about 1.6 sq mm of the transparency). The far right is clearly out of focus. With all that debris of leaves and twigs on the ground, something had to be in focus, somewhere. Firstly, crops from two images where the hairy stem was sharp: Secondly, crops on odd details here and there that happended to be in focus: So far they appear to be equally sharp. I wonder why CZJ ceased production of the Triotar? Maybe they just left triplets to the other manufacturers. The Sonnars evetually became more compact, and some of them were faster (e.g. 85mm/2 that cost US $250 in 1939 and eventually gave way to the 75mm/1.5 Biotar). The 135mm Sonnar never went beyond f:4, in Exakta mount at least. I have a 1939 US pricelist that offers both the Triotar and Sonnar at 135mm, for $132 and $155 respectively (both only imported on request).
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Post by doubs43 on May 25, 2007 11:22:12 GMT -5
"I wonder why CZJ ceased production of the Triotar?"
IMO it was because the 3-element Triotar was perceived by the public as inferior to the newer designs with more elements and better correction for various faults. Zeiss may also have determined that the newer lenses were substantially better and Zeiss was not only quality conscious but had to compete with Leitz and the Japanese too.
Just a couple of educated guesses, really.
Walker
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PeterW
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Post by PeterW on May 26, 2007 21:05:52 GMT -5
I think the reason for Zeiss dropping the Triotar goes a little deeper than it being 'only' a triplet.
If we look at the history of the Triotar, it started life about 1913 or 1914, about the same time as Meyer brought out the somewhat similar Trioplan. The two lenses were rivals for a long time, and both were at their best at around 135mm.
When Bertele designed the ground-breaking Sonnar for the Contax in the late 1920s-early 1930s, one of the difficulties in producing it in focal lengths much longer than 50mm was that, being a six-glass design with uncoated elements, its contrast at long focal lengths wasn't as good as Zeiss wanted.
Bertele's colleague Richter was given the job of redesigning the Triotar as a 135mm lens for the Contax as, with only three glasses, it was thought easier to get higher contrast with uncoated glass.
Where Bertele had a reputation for being uncompromising in his designs, Richter had the reputation of being a compromise artist. He was very skillful in trading off a little in correction of some of the 'less important' aberrations, and maybe a shade of definition at full aperture, to get what he considered was better 'perceived sharpness' with higher edge contrast on black and white film. Similar, in a loose sense, to using 'unsharp mask' in PS.
At that time, when black and white was king, he wasn't concerned so much about colour balance provided he got rid of the major colour aberrations that would have affected its definition with panchromatic film.
Richter's Triotar was a much improved lens compared with the original, but before long Meyer countered with a redesigned 'new' Trioplan as its competitor. The Trioplan was also slightly cheaper than the Triotar, but both lenses sold well.
And there things stayed until the 1950s. Then, with the availability of more modern glass, and improved coatings, Zeiss in West Germany made yet another redesign of the Triotar which improved it still further, particularly with colour film.
The original Carl Zeiss in Jena was at this time 'fighting on two fronts'. It was fighting the 'new' Zeiss in the West over the use of names, and also the formation of VEBs under the East German communist regime. Before long, a 135mm triplet lens appeared under the name Pentacon, but I haven't seen any real evidence as to whether this was a new Zeiss Jena Triotar or a new Meyer Trioplan.
Whichever it was, it sold in the west at a low, probably subsidised, price and photographers were not slow to realise that they could buy a 135mm Pentacon triplet which was equally as good as the Triotar, but at a much lower price.
Coupled with this was the redesign of the Sonnar to use later glasses and coating, which made possible a 135mm Sonnar at f/4 or even f/2 with high contrast and superb definition and colour balance. This, from Zeiss West, had to compete with a new 135mm Sonnar from Jena, but when the use of the name was lost by the East Germans this was called either a Pentacon or sometimes just labelled 'aus Jena'. Whatever its name it was a superb lens, but the name Sonnar still carried a lot of weight with the public, and the East German versions couldn't really compete with that.
When the f/4 135mm Sonnar with early single coating first appeared in late 1936 it cost just over half as much again as the Triotar. The 135 f/2 version cost more than twice the price of the Triotar. This alone put the Sonnar on a much higher plane than the Triotar in the public's perception of things, a perception which stuck right through to the 1950s. I have a feeling that many amateur photographers didn't know or even care how many elements either lens had. The Sonnar was more expensive, so it must be better.
By the mid 1950s, new production methods brought the price of the West German 135mm Sonnar down till it was not really all that much more expensive than the Triotar. Sales of the Triotar fell off, and the decison by Zeiss in West Germany to drop it was, I think, a combination of competition from its own Sonnar and competition from the cheaper East German 135 triplet. The 50mm versions of this new Trioplan were, BTW, called Domiplan.
At least, that's my view of things. Others may differ and I'm willing to be corrected.
PeterW
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Post by doubs43 on May 27, 2007 1:29:21 GMT -5
Peter! Where have you been?! I expected a reply to this yesterday! I was sure that my rather sophmoric explaination would get your attention. As usual, you've provided a far greater in-depth answer than anything I could post and what you've said makes perfect sense. I only have a couple of comments and one is the date you give for lens coating being available to the public. According to the link which will follow, Zeiss developed lens coating in 1935 but it remained a closely guarded secret for military use only until a shipment of coated lenses was sent to Sweden in 1943. Factory coated lenses before and during the war were almost certainly for German military use exclusively. (If it was announced to the public - and it may have been before the military nixed commercial sales of coated optics - I doubt that any were actually made available to them. The new German sidearm P-38, adopted by the Wermacht in 1938, was actually sold in the US commercially before the US military was aware of it!) The link is: www.mir.com.my/rb/photography/htmls/contax_history/history2.htmWhile the trademark name "Sonnar" was protected in most Western nations, it wasn't protected uniformly so CZ Jena continued making lenses marked"Sonnar". I have a 135mm f/4 CZJ marked "Sonnar" as well as another 135/4 marked "aus Jena" and the single letter "S" denoting it's a Sonnar. An odd characteristic of the f/4 Sonnar is that it's f/4 at infinity but almost f/5.6 at 1 meter. When set to f/4 at infinity and focused down to 1 meter, the aperture indication mark will move to about the f/5 position by itself. A third lens I have is a 100mm f/2.8 Meyer-Gorlitz "Trioplan" which is, of course, a triplet. All three lenses are in Exakta mount and I'm ashamed to say that I have yet to give any of them a fair workout. I've been using my M42 lenses recently. The Domiplan is one lens I don't have and really have not had an interest in owning. Most comments I've read about it have been less than "glowing" so I've pretty much ignored it. It seems to have been Meyer's bargain basement lens for those not wishing to buy better or who perhaps couldn't afford better. I doubt that it's "awful" but certainly not in the same league with the Tessar. Walker
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Post by Just Plain Curt on May 27, 2007 7:01:03 GMT -5
Hi Walker, The Domiplan might not be the worst lens I own, but I have 12 of them now and 10 have the aperture mechanism frozen wide open. I'd like to use mine for slingshot ammunition to keep the neighbour's cat out of my flower beds.
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PeterW
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Post by PeterW on May 27, 2007 9:18:56 GMT -5
Hi Walker,
Thanks for your reply. For brevity I over-simplified a little the settlement of the dispute between Zeiss in east and west Germany over the use of trade names. The settlement was quite involved, and the Jena factory could and did use various trade names in certain markets but not others and identical lenses were often labelled differently depending on where they were being sold. I have several Jena-made 135mm Sonnars which are identical except for the labelling.
The change in aperture with focus you mention was originally a Zeiss Jena patent which, as far as I know, was applied only to the Sonnar. The Sonnar which Gene had from me as the prize in our ‘first birthday’ competition had a note with it explaining this and warning that trying to force the aperture to f/4 at certain focus distances could damage the mechanism.
With regard to lens coating, this was not, as the Zeiss website would have us believe, ‘invented’ by Zeiss. But Alexander Smakula, a Ukranian physicist who joined Zeiss in 1934 was the first person to develop a viable industrial process for it. Dennis Taylor, an independent English lens designer who worked a lot for Cooke (he designed the famous Cooke Triplet) was one of the people who observed that a natural tarnish on lenses improved the light transmission. He patented a process for coating lens surfaces as long ago as 1904. It was, however, highly caustic and difficult to apply and, so far as I know, Cooke never used it commercially.
Smakula evolved his process during 1934-1935, and his patent for lens coating was published in 1936. Zeiss announced that the first lenses to which this would be applied were the Sonnars. The 135 f/4 and f/2 coated Sonnars were announced in the 1936 Zeiss trade catalogue, printed in the autumn of 1935, as ‘being available later in 1936’. They were included in the 1936 general catalogue but not specified there as coated.
I have an early-production 1936 Contax II fitted with a coated f/1.5 Sonnar which, according to its serial number, was made in 1938. I used to think that this was possibly coated post-war, but I am told by people with more knowledge of Zeiss history than I have that the coating is original.
I don’t have definite details but I believe that there was a Nazi regime dictate that lens coating was given priority for lenses for military application – bombsights, rifle sights, binoculars etc – but it was not the ‘closely guarded State Secret’ that some writers would have us believe. It was too widely known for that. Coated lenses were sold in relatively small numbers on the civilian market, at least in Germany and, I think, in the UK, from 1937 to early 1939, long before the 1943 export to Sweden.
I have heard that the Nazis were so confident that their planned Blitzkrieg war would be won and finished within two years that despite the armament programme most of Germany’s industry was not put on a strict ‘war production only’ basis for some time after September 1939. Most military production before that was by normal contract.
Also, relations between Zeiss in the east and Zeiss in the west were not as strained as is sometimes portrayed. For example, I understand that until lens production got fully established in the west, many of the lens elements were produced for Zeiss (west) by Carl Zeiss in Jena. Also, a number of Sonnar elements, camera parts and some finished cameras were made in Jena and Dresden for shipping to the Kiev factory in Russia under normal contract, not as reparations.
But I mustn’t get too deeply into my hobby-horse of Zeiss history or I’ll hog the whole board. Anyway, new facts are still coming to light. It wouldn't surprise me if, during the last year or so of the war, the Carl Zeiss Stiftung squirreled away a lot of company documents safe from the Russians, the Americans and the British, with a long-term view of preparing for an unknown future, and let it be believed that they were destroyed in the Dresden fire bombing. I've said before that the Stiftung held the view that recessions, boom times, politicians and regimes come and go, but Zeiss goes on for ever. As indeed it still does.
BTW, the Domiplan wasn’t all that bad a lens, certainly better than the Meritar, but still not the best of post-war triplets, and nowhere near the performance of the Tessar. It was sold on many Praktica models as the bottom of the range lens, but many people paid extra for the optional Tessar instead.
PeterW
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Post by John Parry on May 27, 2007 13:54:39 GMT -5
Yes, I think you're being a bit harsh on the Domiplan. I've found them somewhat basic but quite adequate performers. I have a few, and they all function perfectly.
I wonder if the higher temperatures you encounter over there in summer has caused the grease to congeal more rapidly than it does over here (in the same way that rubberised cloth shutters deteriorate in hot climates).
Regards - John
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Post by doubs43 on May 28, 2007 0:09:12 GMT -5
Peter, once again you've proven to be a fountain of knowledge and it wouldn't bother me if you hogged the board for awhile. I learn when you write! I recall my father saying essentially the same as you concerning the observation that lenses which obtained a "patina" through age were known to produce better contrast than new uncoated lenses and that eventually led to the research that became coating. A 1939 Summitar lens in my collection is coated and would appear to have been factory applied. I bought it thinking I'd get an uncoated version. As I've said, I don't own a Domiplan lens but if both you and John think it to be a decent performer, I can't think of two better testimonials. I'm also certain that Meyer wouldn't have made so many if they'd been really bad. Then again, Kodak sold millions of the Instamatics.......... Walker
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PeterW
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Post by PeterW on May 28, 2007 7:10:22 GMT -5
Thanks for the kind words, Walker.
I too have learned a lot since this board was started, particularly about Japanese cameras. That's one of the great things about this board, and the internet in general - the exchange of information.
PeterW
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SidW
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Post by SidW on Jun 1, 2007 15:03:02 GMT -5
You have all been busy while I was attending to other things, so what a lot of useful stuff there was to read on my return. Thank you PeterW for the Zeiss background. My question about why the Triotar was discontinued was really rhetoric but that wasn't perhaps all that obvious. As with so many things, the people who would have known what really happened and why, like Hummel, have all moved on. The question I would really liked to have asked, but didn't dare to, was whether the Jena 135mm/4 Triotar was seen as a threat to the Jena 135mm/4 Sonnar, if they were performing similarly. I've just seen a late 1950s US pricelist. The Triotar is offered, but not the Sonnar. Now a lot was happening to lenses for the Exakta around then, especially auto aperture releases. Zeiss Jena's first solution was the sprung aperture that needed cocking, and was never applied to the Triotar or Sonnar. The second solution, driven by finger pressure alone, was applied to the Tessar, Pancolar and Sonnar in the 1960s, while the Triotar (and Biotar) was dropped from production. The Sonnar was also redesigned to be more compact. So in a sense, both the Triotar and Sonnar of the 1930s-1950s, 15cm of polished silvery chrome or alloy, were discontnued, but the Sonnar re-emerged. Thank you Walker for pointing out the close-focus behaviour of the aperture. I didn't know that. I knew it happened on the 35mm Flektogon, but the Sonnar was news. Now i don't know what distance the focus ring was at, but the Sonnar aperture closes from f:4 to f:5 from 2m down to 1m. Comparing lenses is not as straightforward as one would like to think. Regarding the Domiplan, that popped up at one point. This is typically the sort of lens that does not do well at the large apertures, but is best at f:8 or f:11. Many of you will know that the Exakta Circle had a triplet competition last year and the winning pictures were all done using the Domiplan. Finally, for comparison, I finished that session with the Hepatica by taking pictures with an EOS EF 50mm/1.8 on a 20D. The following differences should be kept in mind: the lens is comparable to 85mm rather than 135mm, and the extension ring is 12mm. So the scale is very different. And the pixel sizes are different but close - 8Mpx plus for the 20D, 9Mpx plus for the Canoscan 2700F (for the Kodachrome scans). At f:1.8, uncropped image: Crop of the flower centre (100% zoom): The most obvious difference is the unsharp background (but this is aperture 1.8, the others were 4). Another difference is the digital noise or graininess, which is more severe on the Kodachrome scans (the 2700F is the first 35mm scanner by Cannon (or maybe nearly the fist), now 10 years old, and ithe digital noise has never been good), despite the 20D being set to ISO1600 here (I invariably forget to reset it afterwards).
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