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40mm CFE or 903SWC
- Thread starter rcyoung
- Start date
Whether more elements vs. fewer elements makes for a better lens is often relative to the type of lens design in question.
For instance: zoom lenses have a particularly large number of elements compared to primes, and are generally more prone to flare and comparatively aren't as well corrected. In general, as the number of elements in a lens design increases one also increases the number of surfaces that may cause internal reflection-induced flare.
Also compare retrofocus vs. true wide angle lenses (eg., the 40 vs the 38 Biogon): the former tend to have more elements due to the nature of the lens design, but the latter are far better corrected for issues such as barrel distortion.
I am not necessarily taking Q.G.'s side either, the point is that the number of elements in a lens is not necessarily indicative of superiority -- or, for that matter, inferiority either. For ex&le: fast lens in a given focal length generally have more elements than slower ones, but the latter tend to be the sharper of the two. Conversely, as mentioned, the 250 SA has two elements more than the regualar 250 and is comparatively sharper. Similar ex&les can be rattled-off ad nauseum: the point is that it is all relative (to the intent of the design, balancing lens corrections or preferring to correct one specifically -- which generally leads to an increase in another -- etc.) and to argue that more or less elements makes for a better lens is somewhat pointless
For instance: zoom lenses have a particularly large number of elements compared to primes, and are generally more prone to flare and comparatively aren't as well corrected. In general, as the number of elements in a lens design increases one also increases the number of surfaces that may cause internal reflection-induced flare.
Also compare retrofocus vs. true wide angle lenses (eg., the 40 vs the 38 Biogon): the former tend to have more elements due to the nature of the lens design, but the latter are far better corrected for issues such as barrel distortion.
I am not necessarily taking Q.G.'s side either, the point is that the number of elements in a lens is not necessarily indicative of superiority -- or, for that matter, inferiority either. For ex&le: fast lens in a given focal length generally have more elements than slower ones, but the latter tend to be the sharper of the two. Conversely, as mentioned, the 250 SA has two elements more than the regualar 250 and is comparatively sharper. Similar ex&les can be rattled-off ad nauseum: the point is that it is all relative (to the intent of the design, balancing lens corrections or preferring to correct one specifically -- which generally leads to an increase in another -- etc.) and to argue that more or less elements makes for a better lens is somewhat pointless
I am not necessarily taking Q.G.'s side either, the point is that the number of elements in a lens is not necessarily indicative of superiority -- or, for that matter, inferiority either."
But... (and not to argue with you, Wayne. But just so my gainsayers understand) that is my "side", my point!
But... (and not to argue with you, Wayne. But just so my gainsayers understand) that is my "side", my point!
Like most things in technology as in life there are always exceptions to general concepts and practice, there are few absolutes.
Some lens designs use aspherical elements in place of two elements. There is a trade off from perhaps an expensive glass, versus the amount of time to produce the aspherical element. Also, many companies use plastic aspherical lenses, some are even pressed. There are an astronomical number of variables in lens design, from the type and use of glass, on and on, but two major factors also have to be considered during at each choice. Cost and Weight if too expensive or too heavy sales may diminish.
Regards:
Gilbert
Some lens designs use aspherical elements in place of two elements. There is a trade off from perhaps an expensive glass, versus the amount of time to produce the aspherical element. Also, many companies use plastic aspherical lenses, some are even pressed. There are an astronomical number of variables in lens design, from the type and use of glass, on and on, but two major factors also have to be considered during at each choice. Cost and Weight if too expensive or too heavy sales may diminish.
Regards:
Gilbert
In support of both Wayne's and Q.G.'s comments regarding lens elements;
To suggest, or believe, that more lens elements make for a better lens than one with less elements, is akin to suggesting/believing, that just because an engine develops more horsepower, it is a "better" engine than one that develops less. It isn't so.
Wayne's comments regarding both zoom lenses and ultra-fast lenses, are 2 cases in point.
To suggest, or believe, that more lens elements make for a better lens than one with less elements, is akin to suggesting/believing, that just because an engine develops more horsepower, it is a "better" engine than one that develops less. It isn't so.
Wayne's comments regarding both zoom lenses and ultra-fast lenses, are 2 cases in point.
To suggest, or believe, that more lens elements make for a better lens than one with less elements, is akin to suggesting/believing, that just because an engine develops more horsepower, it is a "better" engine than one that develops less. It isn't so.>
Franky, I don't believe your analogy is applicable, but I hope you would choose more horsepower if you needed to evade the semi-truck and trailer ready to broadside you and cement truck on your tail. Nor, is it cast in stone that a larger engine will be less economical. Again, a this is another area of vast variables.
It only applies to apples and apples, ultra-fast to ultra-fast, not biogon to distagon, or telephoto to super wide angle, or f4 to f1. Nor is it an absolute, just as any other measurement of a lens, one may have, less distortion, but exhibit more color fringe problems.
Regards:
Gilbert
Franky, I don't believe your analogy is applicable, but I hope you would choose more horsepower if you needed to evade the semi-truck and trailer ready to broadside you and cement truck on your tail. Nor, is it cast in stone that a larger engine will be less economical. Again, a this is another area of vast variables.
It only applies to apples and apples, ultra-fast to ultra-fast, not biogon to distagon, or telephoto to super wide angle, or f4 to f1. Nor is it an absolute, just as any other measurement of a lens, one may have, less distortion, but exhibit more color fringe problems.
Regards:
Gilbert
If you don't like the horsepower analogy, then perhaps a better ex&le would be Leitz/Leica.
When Leitz set about to improve the performance of their 50mm Summicron lens, the new computation resulted in one less element being utilised when compared to its predecessor.
I think you will agree that this is an "apples and apples" ex&le.i.e. same lens family(Summicron), same focal length, same speed.
I think one would have to agree that the "element" wasn't dropped for "economical reasons" but rather to improve overall performance of an already outstanding lens.
Given that Leitz don't build their lenses down to a price, if performance could have been improved over and above that "new" computation by using an additional element, they would have done so.
When Leitz set about to improve the performance of their 50mm Summicron lens, the new computation resulted in one less element being utilised when compared to its predecessor.
I think you will agree that this is an "apples and apples" ex&le.i.e. same lens family(Summicron), same focal length, same speed.
I think one would have to agree that the "element" wasn't dropped for "economical reasons" but rather to improve overall performance of an already outstanding lens.
Given that Leitz don't build their lenses down to a price, if performance could have been improved over and above that "new" computation by using an additional element, they would have done so.
50 Summicron
"A higher amount of spherical aberration in the 1969 version is mostly responsible for its optical behavior. The designers in those days could not reduce the aberration without resorting to a bigger or more expensive design." from Leica 49 M Lenses.pdf
The early version had 7 elements and the 1969 and 1979 six. New glass compounds and advanced computer computaions were in-place during the later designs.
Frankly, albeit I am not sure yet, a lot of water under the bridge, I think I read about the element concept in a Leica publication. Or about Leica.
Regards:
Gilbert
All cars are brown.
Yes, there are black cars too.
And sure, red and blue ones as well.
And brown is not an 'absolute', there are few absolutes.
Some cars may be silvery grey, and others have been seen that were green.
And even other colours have been reported to occur.
You have to compare apples to apples though. Some of those cars were made in East Asia, others in the U.S., yet others in Europe. So...
And it is generally understood anyway that there are always exceptions to general concepts, right? So, taking that into consideration: all cars are brown.
I believe i read that somewhere lately too.
Or if not that, i'm sure i read something about a car, and it was brown.
So there!
Yes, there are black cars too.
And sure, red and blue ones as well.
And brown is not an 'absolute', there are few absolutes.
Some cars may be silvery grey, and others have been seen that were green.
And even other colours have been reported to occur.
You have to compare apples to apples though. Some of those cars were made in East Asia, others in the U.S., yet others in Europe. So...
And it is generally understood anyway that there are always exceptions to general concepts, right? So, taking that into consideration: all cars are brown.
I believe i read that somewhere lately too.
Or if not that, i'm sure i read something about a car, and it was brown.
So there!
I have got through nearly all the lenses of Zeiss, I found plenty of ex&les to support the fact that better lens has more elements.
For ex&le, Contax Zeiss 120mm f4 has 8 elements
Hasselblad 120mm f4 only has 6 elements
There is simply NO ex&les to support the other way round,ie the better lens has less elements.
Indeed, the more I look, the more I find to support the original theory.
Zeiss F 100mm f2 Makro-planar 9 elements
Contax Zeiss 100mm f2.8 C-Y 7 elements
So far, together with the ones I named before,I quoted 7 lens pairs comparing them with the same focal length they all support the original theory.
On the other hand, I can find no lens pair to show the better one has less elements.
It is not a myth, it is simply a fact that the better one has more elements.
For ex&le, Contax Zeiss 120mm f4 has 8 elements
Hasselblad 120mm f4 only has 6 elements
There is simply NO ex&les to support the other way round,ie the better lens has less elements.
Indeed, the more I look, the more I find to support the original theory.
Zeiss F 100mm f2 Makro-planar 9 elements
Contax Zeiss 100mm f2.8 C-Y 7 elements
So far, together with the ones I named before,I quoted 7 lens pairs comparing them with the same focal length they all support the original theory.
On the other hand, I can find no lens pair to show the better one has less elements.
It is not a myth, it is simply a fact that the better one has more elements.
The following paragraphs are from the 2003 Leica R Lens By Erwin Puts
Leica publication 4rintroduction.pdf
"Vario-Apo-Elmarit-R 1:2.8/70-180mm and has 13 elements with a very high performance profile. The Apo-Elmarit-R 1:2.8/180mm has 7 elements and delivers an even higher performance. This Comparison is not entirely honest, but it does indicate the higher level of effort that is needed for complex zoomlenses. On the other hand can you use these additional elements to improve the quality if you understand the optical system. There is a rule fo thumb lens optical design that says that it is better to distribute the total power of the system evenly over the lens elements. With more elements this is somewhat simpler. In addition the designer will pay attention to the fact that the contribution of every lens surface to the total optical error of the system has to be minimized. This is only feasible if you understand the shapes of the curvatures very well in the error contribution."
"If one could built without restrictions, the optical designer can create aberration free lenses. One can then uses as many lenses as needed and can create many degrees fo freedom, including lens diameters. This can be seen in the field fo micro-lithography where lenses are used for the chip manufacturer and where 30 lens elements for a system are not an exception."
Q
Your sources? or just more Brown Smoke
Gilbert
Leica publication 4rintroduction.pdf
"Vario-Apo-Elmarit-R 1:2.8/70-180mm and has 13 elements with a very high performance profile. The Apo-Elmarit-R 1:2.8/180mm has 7 elements and delivers an even higher performance. This Comparison is not entirely honest, but it does indicate the higher level of effort that is needed for complex zoomlenses. On the other hand can you use these additional elements to improve the quality if you understand the optical system. There is a rule fo thumb lens optical design that says that it is better to distribute the total power of the system evenly over the lens elements. With more elements this is somewhat simpler. In addition the designer will pay attention to the fact that the contribution of every lens surface to the total optical error of the system has to be minimized. This is only feasible if you understand the shapes of the curvatures very well in the error contribution."
"If one could built without restrictions, the optical designer can create aberration free lenses. One can then uses as many lenses as needed and can create many degrees fo freedom, including lens diameters. This can be seen in the field fo micro-lithography where lenses are used for the chip manufacturer and where 30 lens elements for a system are not an exception."
Q
Your sources? or just more Brown Smoke
Gilbert
Here is my eighth quote.
Contax Zeiss 28mm 2.8 C-Y 7 elements
Contax Zeiss 28mm f2.0 C-Y 9 elements the better one
I keep on looking, but there is simply no lens pair I could find to show a better performance with reduced number of elements.I did not decide it myself,I simply CAN'T find any after going through all the Zeiss lenses system.
Is it still a myth ?
Contax Zeiss 28mm 2.8 C-Y 7 elements
Contax Zeiss 28mm f2.0 C-Y 9 elements the better one
I keep on looking, but there is simply no lens pair I could find to show a better performance with reduced number of elements.I did not decide it myself,I simply CAN'T find any after going through all the Zeiss lenses system.
Is it still a myth ?
Joseph,
Yes.
Despite your and Gilbert's effort, it still is.
But i give up. Hadn't i mentioned that?
What can you do, after all, when people claim there is no evidence to the contrary, while such was indeed presented in the very discussion they are participating in?
So again, have fun!
Gilbert,
Before i would even begin quoting references, i would sincererly suggest that you reread the references you have quoted.
Try, and you will be surprised by what you will find they say about this subject.
And to you too i must say that i give up. Believe whatever you want to. And have fun!
Yes.
Despite your and Gilbert's effort, it still is.
But i give up. Hadn't i mentioned that?
What can you do, after all, when people claim there is no evidence to the contrary, while such was indeed presented in the very discussion they are participating in?
So again, have fun!
Gilbert,
Before i would even begin quoting references, i would sincererly suggest that you reread the references you have quoted.
Try, and you will be surprised by what you will find they say about this subject.
And to you too i must say that i give up. Believe whatever you want to. And have fun!
Agree to disagree and move on guys.
What really matters in the end is that we can share actual use of certain lenses and people can sort out whether they fit their photographic needs... which can vary widely.
For ex&le, I can say with personal certainty the Zeiss 180/4 is a spectacular performer and frankly I haven't a clue how many elements it employs nor how many groups they are configured in. I could look it up, and tout Lens element count, and lens chart performance as proof of my opinion, but would be far more influenced if I saw a 40X40 print by a note worthy photographer.
Similarily, Joseph could reference charts and tech documents concerning the superior performance of his Contax Zeiss 120/4 Macro, where I would simply agree with him based on having used the lens extensively for critical commercial work, having never seen a chart on the lens nor care how many elements it may have. Both ways are valid, but my preference is photographs not charts. I chose the lens not because I had compared it's chart performance against that of my Zeiss 120/4CFi, but because it focuses closer with no tubes. The difference between the performance of the 2 lenses is probably there on paper, but most human eyes wouldn't see it ... at least not the eyes that buy my work. However, given the choice I would go with even small gains in imaging performance IF the lenses compared were of equal application stature ... which in the case of the 120s they were not.
The miniscule gains or losses on the part of lens designers are far less important than actual shooting techniques employed, specific need gaps that need to be filled, and a host of other links in the chain of making a photograph ... subjects that tend to be orphans on these threads.
What really matters in the end is that we can share actual use of certain lenses and people can sort out whether they fit their photographic needs... which can vary widely.
For ex&le, I can say with personal certainty the Zeiss 180/4 is a spectacular performer and frankly I haven't a clue how many elements it employs nor how many groups they are configured in. I could look it up, and tout Lens element count, and lens chart performance as proof of my opinion, but would be far more influenced if I saw a 40X40 print by a note worthy photographer.
Similarily, Joseph could reference charts and tech documents concerning the superior performance of his Contax Zeiss 120/4 Macro, where I would simply agree with him based on having used the lens extensively for critical commercial work, having never seen a chart on the lens nor care how many elements it may have. Both ways are valid, but my preference is photographs not charts. I chose the lens not because I had compared it's chart performance against that of my Zeiss 120/4CFi, but because it focuses closer with no tubes. The difference between the performance of the 2 lenses is probably there on paper, but most human eyes wouldn't see it ... at least not the eyes that buy my work. However, given the choice I would go with even small gains in imaging performance IF the lenses compared were of equal application stature ... which in the case of the 120s they were not.
The miniscule gains or losses on the part of lens designers are far less important than actual shooting techniques employed, specific need gaps that need to be filled, and a host of other links in the chain of making a photograph ... subjects that tend to be orphans on these threads.