ELCAN replica lens posts

[Ed Schwartzreic]

I can wrap my head around why it might be more difficult and exacting to center 3 or 4 elements, rather than 8 or 10. When there is successful lens with only a few elements, what can be said about the resulting image, compared to a lens with more elements? Is there theoretical improvement in such things as microcontrast, or whatever advantages there might be with fewer air/glass interfaces?

Can someone with expertise here comment?

Ed

 

[Freakscene]

I can wrap my head around why it might be more difficult and exacting to center 3 or 4 elements, rather than 8 or 10. When there is successful lens with only a few elements, what can be said about the resulting image, compared to a lens with more elements? Is there theoretical improvement in such things as microcontrast, or whatever advantages there might be with fewer air/glass interfaces?

Can someone with expertise here comment?

In theory, fewer elements means less transmission loss. Air-glass interfaces were traditionally more lossy than glass-glass cemented surfaces. My father, who is 91 and learned optics in the 1940s and 50s, was trained that less was best. But modern glass types, and especially coatings, pretty much make this issue moot (although a lot of lenses have t stops that differ from their f stops) and more elements and different glass types allow better correction of aberrations. So now you have 13 element in 8 group normal lenses, with performance that would have been unthinkable even 20 years ago.

Marty

 

[Erik van Straten]

different glass types allow better correction of aberrations

Don't forget that environmental legislation in many countries now prohibits the use of lead in the glass, the so-called "flint glass". This forces the designers to switch to aspherical glass surfaces or to use more lens elements. I don't think that makes the lenses any better. Less is better! Give me my flint back!

Erik.

 

[kram]

Modern aspherical surfaces and coating, flint glass, few elements...it's getting to much, I am going to take a cold shower😀

 

[Freakscene]

Don't forget that environmental legislation in many countries now prohibits the use of lead in the glass, the so-called "flint glass". This forces the designers to switch to aspherical glass surfaces or to use more lens elements. I don't think that makes the lenses any better. Less is better! Give me my flint back!

Flint glass was a good (but not great) option in the 1950s. There are vastly better optical glasses made now that can be manufactured without discharging toxic products. Note that lead is still used in plenty of things - the main problem with flint glass is that it is very difficult to make it without releasing lead to the atmosphere. It has no special properties and can be replicated with other glass types of the same refractive index - the problem for projects like the recent replicas of Leitz lenses of the 1950s is that modern glass sometimes needs to be a different thickness for the same effect, so the lens has to be recomputed. This makes life difficult if what you are trying to build is an exact replica. It is also easier to replicate the pretty ordinary colour transmission characteristics of the day with older glass types.

Marty

 

[f.hayek]

This makes life difficult if what you are trying to build is an exact replica. It is also easier to replicate the pretty ordinary colour transmission characteristics of the day with older glass types.

Marty

'Difficult' is all relative given today's supercomputing capabilities. Leica also has the formulae to its older special glass, in contrast to the Knockoff "Artisans", whose word everyone takes for the presence of flint glass in the 35. Recalculated element formulation & thicknesses along with modern coatings make even Leica's re-releases more official homage than perfect recreations. All of which does not diminish the substantial achievement of LLL in the 8-element project. But whereas LLL has completely different mechanicals underneath the nacelle, Leica did a bang-up job with the 28 Summaron & the 50 Noctilux, glass and authentic mechanicals so hat-tip to them.

Their long-anticipated 35 Summaron ƒ/2.8 should be a most exciting release.

 

[Freakscene]

'Difficult' is all relative given today's supercomputing capabilities. Leica also has the formulae to its older special glass, in contrast to the Knockoff "Artisans", whose word everyone takes for the presence of flint glass in the 35. Recalculated element formulation & thicknesses along with modern coatings make even Leica's re-releases more official homage than perfect recreations. All of which does not diminish the substantial achievement of LLL in the 8-element project.

But Leica did a bang-up job with the 28 Summaron & the 50 Noctilux so hat-tip to them.

I don’t mean lens design difficulties; that is simple, and a reasonably powerful desktop is more than enough to do redesigns quickly provided you have adequate software or programming capacity. I mean physically reconfiguring an exact replica of the objective and all its elements with different lens thicknesses to the original - that is hard because of the physical redesign required and the realities of the materials involved.

It is straightforward enough to plan a redesign from measurements of refractive index and curvature. You can do this from a good sample of the original lens. Essentially all each element does is refract light a certain amount, but modern glass types of equivalent refractive index to 1950s flint glass or any other historical glass types have different colour transmission characteristics to 1950s glass types.

I bought two of the LLL eight element replicas. What glass they have doesn’t worry me, but I had to recollimate both of them because they were hopelessly, hopelessly out of alignment when I received them, and I got no reply when I contacted LLL to let them know that the lenses were horribly poorly put together. I was so annoyed by the whole thing that I sold them both, but then was pleased by the large profit I made, which soothed my annoyance at the initial problems. But only a bit.

The 28 Summaron and the 1.2 Noctilux are great replicas. I would expect that of Leica. But I also prefer the 28 Summicron and 50 Summilux asph in use.

Marty

 

[f.hayek]

I bought two of the LLL eight element replicas. What glass they have doesn’t worry me, but I had to recollimate both of them because they were hopelessly, hopelessly out of alignment when I received them, and I got no reply when I contacted LLL to let them know that the lenses were horribly poorly put together. I was so annoyed by the whole thing that I sold them both, but then was pleased by the large profit I made, which soothed my annoyance at the initial problems. But only a bit.

Cool you have a collimator! But what a pain. Zero QC @ LLL; it's the gross indifference to their customer base I don't get.

The 28 Summaron and the 1.2 Noctilux are great replicas. I would expect that of Leica. But I also prefer the 28 Summicron and 50 Summilux asph in use.

Agreed, but it does fill a niche for a certain 'look' unobtainable from modern designs but precludes the gamble on a 65 year-old optic that may be hopelessly fogged (this happened to me with an 8-element) or needing a costly overhaul (as happened to me with a 50 Rigid).

 

[Freakscene]

Cool you have a collimator! But what a pain. Zero QC @ LLL; it's the gross indifference to their customer base I don't get.

I have access to a university optics engineering lab, it has everything you need and then some.

Agreed, but it does fill a niche for a certain 'look' unobtainable from modern designs but precludes the gamble on a 65 year-old optic that may be hopelessly fogged (this happened to me with an 8-element) or needing a costly overhaul (as happened to me with a 50 Rigid).

Yes, absolutely. It would be great if Leica made a new rigid 50 Summicron - I’d like that more than anything. Just take the irritating infinity lock off it.

Marty

 

[Rob-F]

I can wrap my head around why it might be more difficult and exacting to center 3 or 4 elements, rather than 8 or 10. When there is successful lens with only a few elements, what can be said about the resulting image, compared to a lens with more elements? Is there theoretical improvement in such things as microcontrast, or whatever advantages there might be with fewer air/glass interfaces?

Can someone with expertise here comment?

Ed

In theory, fewer elements means less transmission loss. Air-glass interfaces were traditionally more lossy than glass-glass cemented surfaces.
Marty

And another benefit of minimizing the number of lenses, that hasn't been mentioned yet, is the improvement in contrast. It is possible that even if a lens with fewer elements may not be as sharp in resolving power, the images may look sharper owing to the greater contrast. Some lenses with only four elements in three groups, the Zeiss Tessar and the Leitz Elmar, have earned their place in history partly because of this. They are good, not in spite having fewer elements; rather, they are good because of having fewer elements.

 

[teddy]

A replica of a very rare and expensive Leica lens with special performance is maybe a good target to have. The 50/1.2, as it has been mentioned many times before, would have been a tempting offer. Another "micro Nikkor" would be great. A Summaron 35/2.8 too! I missed this lens somehow.

The Summaron has a magic - superb clarity in the centre with high resolution then the outer most corners have veiling flare with excellent sharpness but this tapering of characteristics creates bliss for the photographic connosseur.

I've had five of them, kept the best one. I own a Summaron 35/2.8, Summicron 35/2 and the 35 Replica.

 

[raid]

Such threads have become less useful to me. I have gotten tired of the replica business overall.

 

[raid]

The Summaron has a magic - superb clarity in the centre with high resolution then the outer most corners have veiling flare with excellent sharpness but this tapering of characteristics creates bliss for the photographic connosseur.

I've had five of them, kept the best one. I own a Summaron 35/2.8, Summicron 35/2 and the 35 Replica.

No replica can replace the special feel of a Leica or Zeiss lens (or similar). I have an 8e Summicron and a replica, because I was curious once. I also own a Zeiss ZM 35/2 and a Canon 35 (1.5, 1.8, 2). I also have a Summilux 35/1.4 and a Nikon 35/1.8ltm. Each of these vintage lenses are special to me. They have a history to tell.

 

[Emile de Leon]

Trouble in...LLL..paradise...

 

[raid]

Maybe this thread should be closed.

 

[Erik van Straten]

No replica can replace the special feel of a Leica or Zeiss lens (or similar). I have an 8e Summicron and a replica, because I was curious once. I also own a Zeiss ZM 35/2 and a Canon 35 (1.5, 1.8, 2). I also have a Summilux 35/1.4 and a Nikon 35/1.8ltm. Each of these vintage lenses are special to me. They have a history to tell.

I agree with you, Raid, but it is undeniable that also the replica 8E has a history to tell, however short and however strange it may be.

gelatine silver print (replica 8e) leica mp

Erik.

 

[raid]

Erik, you would take excellent photos with any lens you happen to use.

 

[Erik van Straten]

Thanks Raid! All the best for you and your family.


Erik.

 

[kram]

1700 cad works out as £973. VM 50mm f2 APO sells for £1070. It is a tough choice to make, I will sit down and think about it...

 

[kram]

Rendering of a decentered 4 element 1970s replica lens..
Guys I would love the rep ELCAN to be a great thing, but something tells me otherwise. Come on LLL tie in with decent distributors who offer warranty.