Lotusm50 wrote:
You haven't read alot of Zeiss materials. Contax materials only rarely spoken about a optical design element. Go and read all the ZF lens materials -- they say NOTHING about the elements in their optical designs, nothing about flaoting elments, nothing about ultra-low dispersion glas, nothing about ashpheric elements, nothing. Zeiss has been using aspheric elements since the 1930's yet never ever really mentioned it -- and they still really don't. Zeiss doesn't have to shoot about how they designed the lens -- the proof is in the performance. That is what matters, that is what they talk about and that is how they sell their lenses -- not whether it has 2 or 3 aspheric elements and one that floats. Your Hassy materials are a rare case when they did talk about an optical element. It is a very lonely exception to a very long standing practice -- a practice that continues today. ...Show more →
NONE of the quotes listed below are in regards to Hasselblad AND the statements are as literal as can be about lens design specifically and the use of special types of Glass AND Floating Elements. This is completely opposite of your statement.
Taken from Zeiss PDF's:
Contax N Vario-Sonnar 24-85
"To achieve this high image quality along with relative
compactness, this lens uses elements made of special
fluor-crown glass with anomalous partial dispersion,
and additional aspheric surfaces."
Contax Yashica Distagon 21mm
"This new lens, however, is not a modification of the
existing wide-angle lenses, but a totally new design..
All of the possibilities of correcting residual
chromatic aberration were utilized to the full. The
systematic use of glass featuring extreme
anomalous partial dispersion combined with
high-index glass resulted in a level of correction
never achieved before. The incorporation of an
internal focusing system and a floating element
ensures that this new lens delivers superior image
quality in all conditions."
ZM Distagon 15, a Current lens with a Current statement!
"In order to achieve the unique performance
level, the lens’s complex design incorporates floating
elements, a total of 11 elements (with one aspherical
surface) comprising exotic optical glasses such as high-
refractive-index barium dense flint and flour crown
with anomalous partial dispersion."
Perhaps if Zeiss are not mentioning these specifics as regards ZF lenses but do mention them with every other mount(including the current ZM mount), then the current ZF lenses are just not that exotic at present.
Tariq Gibran wrote:
Perhaps if Zeiss are not mentioning these specifics as regards ZF lenses but do mention them with every other mount(including the current ZM mount), then the current ZF lenses are just not that exotic at present.
But they don't mention them with every other lens line. You have mentioned 3 lenses out of a few hundred. As I said with Contax it was "rarely" done. To suggest or imply that the ZF lenses are less "exotic" (whatever that means -- floating elements, aspheric surfaces, and ULD glass are really not "exotic" any more, Sigma seems to exclaim their presence in every lens they make) than 10 and 20+ year old Zeiss designs for Contax because they don't mention the type of optical elements they use in the designs is patently ludicrous.
Lotusm50 wrote:
But they don't mention them with every other lens line. You have mentioned 3 lenses out of a few hundred. As I said with Contax it was "rarely" done. To suggest or imply that the ZF lenses are less "exotic" (whatever that means -- floating elements, aspheric surfaces, and ULD glass are really not "exotic" any more, Sigma seems to exclaim their presence in every lens they make) than 10 and 20+ year old Zeiss designs for Contax because they don't mention the type of optical elements they use in the designs is patently ludicrous.
Simply step out of the ZF line and read the material at Zeiss.com concerning their other lens lines, particularly the specific information they provide on the lenses they make for Cinematography. There you will also find Zeiss touting why technically their lenses are superior and how they have designed them to be so using specific technologies. This IS the most common selling/marketing tool that Zeiss use to sell their lenses. Your statements are just simply disproven categorically if you read through the information at Zeiss.com. But thats obvious when first you state that Hasselblad was the sole exception for this but then other examples are demonstrated. In fact, examples of Zeiss touting their technical design abilities can be found in the majority of the lens lines. Where Zeiss seems not to mention this is with specific lenses which are not manufactured in house. It is clear that Zeiss are not comfortable with and or that Cosina is not capable of manufacturing the most exotic and complex designs of Zeiss which is why certain lenses are still made in house. This has been stated here quite nicely by Edwin Puts:
"Most new Zeiss-designed lenses are made in the Cosina factory, but not the Sonnar 2/85mm lens. The design requires a level of manufacturing quality that Cosina does not (yet) possess and this lens (as is the case with the 2.8/15mm) is hand assembled in Oberkochen. Here we se a glimpse of the differences in manufacturing technology and production quality between Zeiss (and Leica) and Cosina. The Cosina lenses are very good and quite reasonably priced, but to keep the costs to a level that profit is still possible, one can not demand from these lenses the utmost in manufacturing quality and material quality: hold the lens surface tolerances to the smallest possible amount, use the most demanding glass types and assemble the elements in mechanical mounts with microscopic precision."
Lotusm50 wrote:
Zeiss doesn't often talk freely about elments of its lens design. There is also no mention anywhere about aspheric elements or ultra-low dispersion glass, or anything else. Zeiss not mentioning a design element doesn't necessarily mean that it doesn't have that element. It's just typical that they not say anything about it.
The reference to floating elements in Zeiss' data is conspicuous by its absence. I think it would be the first Zeiss design that deploys it, but doesn't say so. All the 'FLE' Hasselblads . . . the 28/2 and the 21/2.8 . . . and, in the new ZF lineup, the 50/2 Makro. The evidence is pretty compelling. This speculation should imminently become redundant, when we receive word from Zeiss.
Lotusm50 wrote:
Zeiss does claim that the lens "incorporates the latest optical design". They also claim, and this is supported by the published MTF's, that the ZF 25mm Distagon, "features the very highest image sharpenss to the very edges of the image format even at full aperture".
I too was struck by the careful choice of wording: 'sharpness to the very edges of the image format'. . . the close range corner softness that FLE would have improved is 20mm from the frame centre: well outside the Nikon digital image format for which the lens is obviously intended. Understandably, they appear not to have designed the lens for the dwindling-to-vanishing number of Nikon 35mm film users – or 1Ds owners.
This assuming that my sample is not imperfect, and there is no adaptor problem, and there is no floating element . . .
Cinstance wrote:
Regarding the floating element design, at least in the case of C/Y lenses, Zeiss mentioned it in every lenses that have it. At least it is benificial in commercial sense, and isn't much leaking technically by just mentioning it.
T
See the new 100 mm Macro goes as close as the old 100mm Macro, about 44 cm, but only the older c/y mentiones the FLE, thats why I think they both use an internel focus mechanism.
hubsand wrote:
I too was struck by the careful choice of wording: 'sharpness to the very edges of the image format'. . . the close range corner softness that FLE would have improved is 20mm from the frame centre: well outside the Nikon digital image format for which the lens is obviously intended. Understandably, they appear not to have designed the lens for the dwindling-to-vanishing number of Nikon 35mm film users – or 1Ds owners. .
But the published MTF's do suggest that the lens is sharp 20mm from the frame center. Zeiss does take pains to indicate that these lens are designed for full frame film cameras as well as digital. While it is clear that one of the intended uses of the ZF lenses would be Nikon crop digital cameras, there are other intended uses as well, Nikon mount film cameras, and the the Sinar M modular camera (which can use a full frame 35mm sensor as well as a medium format one) is featured in their information materials.
How "close" were your test images? At what focus distance were they captured? They would seem to be done at a "normal" distance, perhaps close to infinity, rather than a "close" distance such as 50cm. I would suggest that whether it has a FLE or not, does not necessarily preclude performance. It's inclusion is irrelevant, what matters is how is performs. As far as I know, we have not seen sample images from the lens at close distances (something the lens was designed for) where, as you suggest, the inclusion of a FLE in the design can help.
Tariq Gibran wrote:
Simply step out of the ZF line and read the material at Zeiss.com concerning their other lens lines, particularly the specific information they provide on the lenses they make for Cinematography. There you will also find Zeiss touting why technically their lenses are superior and how they have designed them to be so using specific technologies. This IS the most common selling/marketing tool that Zeiss use to sell their lenses. Your statements are just simply disproven categorically if you read through the information at Zeiss.com. But thats obvious when first you state that Hasselblad was the sole exception for this but then other examples are demonstrated. In fact, examples of Zeiss touting their technical design abilities can be found in the majority of the lens lines. Where Zeiss seems not to mention this is with specific lenses which are not manufactured in house. It is clear that Zeiss are not comfortable with and or that Cosina is not capable of manufacturing the most exotic and complex designs of Zeiss which is why certain lenses are still made in house ...Show more →
I am sorry to inform you, but nearly ALL Zeiss 35mm lenses (and many MF lenses) have not been made by Zeiss for a long time. Some of those "exotic" lenses you mention were actually made by Kyocera. The lenses made in Germany are also low-volume lenses and that may also have something to do with it. Right now, only the ZM 85mm and 15mm (expensive, low volume lenses) are made in Germany (actually the ZM 15mm design proved to be unable to be reliably made no matter where they tried and is being totally re-designed -- so that move to make the complex, exotic 15mm in Germany proved to be more off a design problem than a Cosina capability problem). Further, for several years before the ZM/ZF/ZS lens lines ever came in to being, NO 35mm lenses were made in Germany by Zeiss. Finally, whether Cosina aseembles the most complex specialty lenses or not, doesn't mean they are not or can not produce a lens with FLE or other "exotic" elements -- most of these things are old hat these days, even for Cosina.
Edited by Lotusm50 on Jan 31, 2007 at 09:05 AM GMT
Lotusm50 wrote:
How "close" were your test images? At what focus distance were they captured? They would seem to be done at a "normal" distance, perhaps close to infinity, rather than a "close" distance such as 50cm. I would suggest that whether it has a FLE or not, does not necessarily preclude performance. It's inclusion is irrelevant, what matters is how is performs. As far as I know, we have not seen sample images from the lens at close distances (something the lens was designed for) where, as you suggest, the inclusion of a FLE in the design can help.
Lotusm50 wrote:
I am sorry to inform you, but nearly ALL Zeiss 35mm lenses (and many MF lenses) have not been made by Zeiss for a long time. Some of those "exotic" lenses you mention were actually made by Kyocera. The lenses made in Germany are also low-volume lenses and that may also have something to do with it. Right now, only the ZM 85mm and 15mm (expensive, low volume lenses) are made in Germany. And for several years before the ZM/ZF/ZS lens lines came in to being, NO 35mm lenses were made in Germany by Zeiss. Further, whether Cosina aseembles the most complex specialty lenses or not, doesn't mean they are not or can not produce a lens with FLE or other "exotic" elements -- most of these things are old hat these days, even for Cosina. ...Show more →
I am aware that Kyocera manufactured most of the Zeiss lenses for the Contax. It does appear that Kyocera had greater capabilities than cosina as regards technical abilities to put a very complex design into production and mantain the integrity of that design. Out of curiousity, exactly which Medium Format lenses are you referring to? Contax 645? Kyocera again? I know Hasselblad CF/CFi were all made by Zeiss in Germany if the lens said Zeiss on it. Zeiss's newest Medium Format Autofocus lenses made for Sinar are also made in house in Germany as reflected by their outrageous price. Interestingly, your Sigma example earlier demonstrates exactly what Zeiss is probably concerned about as regards putting very complex designs into production. Sigma Sample variation is Legendary. I think Zeiss is very warry of going down that road. Its one thing to make complex lenses with exotic materials such as Canon, Sigma, and others do but its quite another to do so to such a high Production standard that one can be gauranteed that the lens you buy is equel to the capabilities of the disign sample to sample. Even Canon fails here.
hubsand wrote:
I too was struck by the careful choice of wording: 'sharpness to the very edges of the image format'. . . the close range corner softness that FLE would have improved is 20mm from the frame centre: well outside the Nikon digital image format for which the lens is obviously intended. Understandably, they appear not to have designed the lens for the dwindling-to-vanishing number of Nikon 35mm film users – or 1Ds owners.
This assuming that my sample is not imperfect, and there is no adaptor problem, and there is no floating element . . .
Given Zeiss's attitude to digital, and their statements that the new range of lenses challenge even the best of todays films I doubt they would have designed a lens specifically for a crop sensor without mentioning it.
Tariq Gibran wrote:
I know Hasselblad CF/CFi were all made by Zeiss in Germany if the lens said Zeiss on it. Zeiss's newest Medium Format Autofocus lenses made for Sinar are also made in house in Germany as reflected by their outrageous price.
My brother-in-law is a sales rep for outdoorsman supplies. He sells exotic rifle scopes and binoculars by German companies like Swarovski and Zeiss. As a result, he is privvy to some of those manufacturer's processes and procedures. You would be surprised at how much stuff is jobbed out.
I have a hunch that many of the Hasselblad Zeiss lenses were jobbed out to a local German optical house for assembly, and when the Hasselblad Zeiss line came to an end, that jobber simply folded up. Perhaps the lenses for the Sinar-m are so outrageously priced because they are actually now done in house, evidenced by the doubling in price of the 40mm. As the Hasselblad CFE IF 40mm, it retailed for $5000. Now as the Sinar-m AF 40mm, it retails for $10,000. Quite a jump for the mere addition of autofocus/auto aperture and the elimination of the mechanical shutter/mechanical aperture.
Tariq Gibran wrote:
I am aware that Kyocera manufactured most of the Zeiss lenses for the Contax. It does appear that Kyocera had greater capabilities than cosina as regards technical abilities to put a very complex design into production and mantain the integrity of that design.
"It does appear". I don't think that is the clear at all. You really don't know and have no information to make thgat judgement other than yourt own subjective veiwpoint. Why are so so dissmissive of Cosina? Their Voigtlander Bessa lenses provide 95% of the performance of current Leica M lenses at a quarter of the cost. They are very highly regarded (and Zeiss didn't even design them). All of the Cosina lenses for Zeiss, at least by all reports, appear to be very well made -- cetainly the ones I've seen are.
Tariq Gibran wrote:
Out of curiousity, exactly which Medium Format lenses are you referring to? Contax 645? Kyocera again? I know Hasselblad CF/CFi were all made by Zeiss in Germany if the lens said Zeiss on it. Zeiss's newest Medium Format Autofocus lenses made for Sinar are also made in house in Germany as reflected by their outrageous price.
Yes the Contax 645 lens were made in Japan and in many cases were VERY complex (check out the 35/f3.5 Distagon). It is also not clear than since the Hassy lens were made in Germany that they were actually made by Zeiss in the Zeiss factory. Regardelss of wherethey are made they are all Zeiss lenses and must pass Zeiss quality controls. Zeiss does not maintain it's own significant camera lens production facilities. They may indeed be making the Sinar AF lenses, but given the tiny volumes and high prices involved they could all be hand made in Zeiss' labs.
Tariq Gibran wrote:
Interestingly, your Sigma example earlier demonstrates exactly what Zeiss is probably concerned about as regards putting very complex designs into production. Sigma Sample variation is Legendary. I think Zeiss is very warry of going down that road. Its one thing to make complex lenses with exotic materials such as Canon, Sigma, and others do but its quite another to do so to such a high Production standard that one can be gauranteed that the lens you buy is equel to the capabilities of the disign sample to sample. Even Canon fails here.
OK. So Zeiss is now wary of being shown to be no better than Sigma. Also, what exactly do you mean by "complex", or "exotic"? A 10 element 25mm lens that focuses down to 18cm, that from the looks of it has aspheric surfaces, and perhaps other un-named features is nothing if not "complex". I reject the idea that only Leica and Zeiss in Germany can reliably make "complex" lenses. Certainly Sigma has problems (but the wasn't the point about Sigma -- the point was that the use of all these so-called "exotic" features (FLE, ULD, ASPH) is commonplace these days, even with the lower tiers of manufacturers, and including the features, obviously does not necessarily make a lens perform well.) You argument boils down to essentially this. Zeiss is making non-competitive, old technology, simple (non-complex) lenses because that is the only thing they can reliably make. Quite frankly, that it just laughable as well as baseless.
Lotusm50 wrote:
What, where on earth did you come up with that? Anyway, I have stated my points clearly, quoted Zeiss PDF's concerning their much used marketing of specific lens design and special elements and have linked to collabariting information regarding the difference with Zeiss in house manufacturing and farmed out manufacturing to Cosina. Thats about as clear as I can be. Sorry if you just don't agree. We will just have to agree to disagree on move on.
lol this thread is gettin' funny yet none of us here are involved in designing the lens or involved in production management of the Zeiss ZF lenses
Hopefully you guys won't forget that the ZF lens are optimized for a Nikon dslr ~ just like Nikkor lenses are optimised for Nikon bodies. The only way to nail this lens is to test it on a 35mm Nikon DSLR and I hope that's a D3 series body
As always a big thank you for the test, these are unbeliveably helpful when considering the universe of lenses out there.
Based on your tests of the 25 and 85 ZF's against the Canon L equivilants I, personally can't see much of an argument for buying the ZF lenses. Of course thats my personal assesment - I like AF, brighter viewfinder, more shooting options, and readily avaialable, reasonably priced repair services. It's interesting to note the Zeiss faithful getting thier panties in a bunch over the results.
Perhaps a second sample will provide different results...who knows. In the end I don't think Zeiss has assigned much import to the type of folks gathered here (cmon guys we really are the minority in the vast sea of photographers out there). The large majority of sales is likely in the far east, not in europe and the USA and will go to collectors (with crop bodies) less concerned with obsessive pixel peeping.
I've been reconsidering the pictures in the light of several people disagreeing with my preference for the ZF25 over the 24L in certain places. And I'd like to say that they're wrong. Even this, perhaps non-optimal, ZF25 is still a tiny notch above the C24L overall.
Without setting the same shot from a C24L right next to it, it's hard to be sure, but this looks rather more like the level of performance we were expecting, and perhaps better than the sample Zeiss sent me. This, incidentally, was shot with a cheap Chinese adaptor.
In the test, I noticed either horrible oversharpening or JPEG artifacts, but I suspect that there are both. I would tend to keep the sharpening to a minimum and save at the highest quality.
the Canon, to my eyes, walked all over the Zeiss in this comparison. I completely disagree with the statement that f 8 and above is more important than f 2.8 - 5.6 (not to mention the ABSOLUTE dominance of the Canon between 1.4 and 2.8)
The Canon demolishes the Zeiss in the corners and only slightly loses out in the center up to f8. If the points system were a 1-10 scale, the corners at f4 would stand with the Canon at a 8 points and the Zeiss at 1 point. This is significant, and I'm surprised the Zeiss was listed as the winner but I understand there is more to it than can be explained over the web.
john - your weighting scale is different ... so the conclusion you come to is different. see other threads here where we discuss and agree that people have to factor in their own weights. for some people f8 is the most important thing and carries a significant portion of the weighting. for others it isn't so dominante. you have to take each individual test, apply your own weights, and then determine your own winner.
yet none of us here are involved in designing the lens or involved in production management of the Zeiss ZF lenses 